Beijing city fortifications

The city wall of Beijing was a fortification built around 1435. It was 23.5 km long. The thickness at ground level was 20m and the top 12m. The wall was 15m high, and it had nine gates. This wall stood for nearly 530 years, but in 1965 it was removed to give way to 2nd Ring Road and the loop line subway of Beijing. Only in the southeast, just south of Beijing Railway Station, stands one part of the wall. Three gates of the city wall are also intact (Desheng Gate, the Yongding Gate and Zhengyang Gate).

Beijing was the capital city of the last three dynasties (the Yuan, Ming and Qing) as well as two northern dynasties (the Liao and Jin) in the history of China, as such, Beijing is often referred to as an "ancient capital of Five dynasties" (五朝古都). It had an extensive fortification system, consisting of the Palace city, the Imperial city, the inner city and the outer city. Specifically including the many gate towers, gates, archways, watchtowers, barbicans, barbican towers, barbican gates, barbican archways, sluice gates, sluice gate towers, enemy sighting towers, corner guard towers and moat. It had the most extensive defense system in Imperial China.

After the collapse of the Qing Dynasty in 1911, Beijing's fortifications were dismantled one by one, the Palace city has remained largely intact, becoming the Palace Museum; the Imperial city only has Tian'anmen and several sections of imperial city wall remaining intact; the inner city with Zhengyangmen's gate tower and watchtower, Deshengmen's watchtower, the southeastern corner guard tower, and a section of the inner city wall near Chongwenmen remaining intact; and nothing of the outer city remaining intact, with Yongdingmen completely reconstructed in 2004.

History

The forerunner of the Beijing city of the Ming and Qing dynasties was the Khanbaliq city of the Yuan Dynasty that was built in 1264. The design of the Khanbaliq city followed the book Zhouli, in that the rules of “9 vertical axis, 9 horizontal axis”, “palaces in the front, markets in the rear”, “left ancestral worship, right god worship” were taken into consideration. It was broad in scale, strict in planning and execution, complete in equipment.

In August of the first year of the Hongwu era (1368), Ming Dynasty general Xu Da successfully invaded the city of Khanbaliq. Due to the last khan of Yuan, Yuan Shundi escaping from the city without defending, the city received no damage, and remained untouched [《明史纪事本末》、《纲鉴易知录》卷八] . However, because Khanbaliq’s fortification system was too great in size, which is a disadvantage for the defence of the city during a siege, Xu Da ordered the city’s northern walls rebuilt 2,8 kilometres south of the original. Laying waste to the Yuan’s planned expansion areas in the north of the city. At the same time, an extra layer of brick wall was added to the newly built northern walls with the bricks from the Yuan original, further strengthening the city’s defences《北京城垣的保护与拆除》,《北京规划建设》1999年第2期 ] . In 1370, Ming Taizu Zhu Yuanzhang granted to his fourth son Zhu Di the title King of the Yan dependency with capital at Beiping (present-day Beijing). In 1379, the new Palace of the King of Yan was completed, and Zhu Di moved in the following year.

In 1399, Zhu Di started the Battle of Jingnan; in 1402 he took the title of emperor; in 1403 he changed the city name of Beiping (“northern peace”) to Beijing (“northern capital”). In 1406 (4th year of the Yongle era), he started the plan to move the capital from Nanjing to Beijing. At the time, Beijing was merely the capital of Zhu Di’s dependent kingdom of Yan, and being such that the city’s fortifications were not very extensive. When Zhu Di named Beijing as the new capital, he realised that the city’s fortifications needed extensive expansion and reconstruction work to meet the requirements of the defence of a nation’s capital and to withstand sporadic Mongol intrusions from the north. This marked the beginning of the Ming sections of Beijing’s fortifications of which parts still exist today.

From 1406 onwards, upon the foundations of the Yan King's Palace, construction work on the Xinei ("inner west") began. It was finished the following year. In 1409, Jianshouling was completed at Mount Tianshou in the Changping district. Beginning in 1416 (14th year of the Yongle era), construction work began on the Beijing Imperial Palace complex, in imitation of the style of the original Nanjing Imperial Palace complex. Completing the Forbidden City's halls, palaces, and pavilions, Taimiao, Ancestor Hall, Mount Wansui, Taiye Pond, Residences of the Ten Kings, Residences of the Imperial Princes, Residences of the Officials, and the Drum and Bell Towers. At the same time, the original southern city walls of the Yuan Khanbaliq were moved south by 0,8 kilometres, in order to allocate the space needed for the future Imperial City complex. In 1421 (19th year of the Yongle era), the capital of Ming Dynasty China was officially moved from Nanjing ("south capital") to Beijing ("north capital"). Subsequently, the Temples of the Heaven and the Earth along with the mountains and valleys were built in Beijing's then southern suburbs. There are some sources indicating that the Beijing City's central axis of the Ming dynasty was moved eastwards from that of the Yuan Khanbaliq. This was to superstitiously subdue the previous (Yuan) dynasty's Qi (As new Qi comes from the east where the sun rises daily) [见 [http://www.artwork.com.cn/beijing/wh/009.asp 明清时期的北京城] 。 此派观点认为，明代兴建北京宫殿时，将中轴线向东平移了150米左右，将元代宫殿中轴置于西方方位、即“白虎位”或“杀位”上，在风水学说中为魇镇前朝王气的做法，同时也为在紫禁城西侧开挖筒子河提供了空间。今北京故宫内武英殿东边的断虹桥即元代宫城崇天门前的周桥，其依据为该桥桥面原极华丽，桥面上有汉白玉石雕云龙瑞兽，此做法在辽、金、元宫殿中只用于宫城正门之前居中位置的御桥。断虹桥桥面花纹在明初被朱元璋下令凿平。此外，从明清北京城市中轴线的位置来看，其轴线位置偏东，正阳门与崇文门之间的距离要小于正阳门与宣武门之间的距离。] .

The second expansion of Ming dynasty Beijing occurred between 1436 and 1445 on the orders of Emperor Ying of the Ming dynasty. Major expansion works included: Addition of an extra layer of bricks on the interior side (i.e., facing the city) of the city walls; digging and filling in with water of Taiye Pond's southern pond; construction of nine major city gates' gate towers, barbicans, and watchtowers; construction of the four corner guardtowers; Setting up a Paifang on the outside of each of the major city gates; Replacing the wooden bridges of the city moats with stone bridges. Sluices are then built under the bridges, and revetments are built of stones and bricks to protect the moat's embankment.

The newly expanded Beijing city wall and moat system was 45 lis (approximately 22,5 kilometres) in perimeter, forming a formidable defence for the city. The Imperial Tombs were built on the far outskirts of the city, as well as Changping city, supply city, interior Great Wall sections and other distant fortifications for the protection of Beijing city during a siege.

After the completion of Beijing city as the new capital of Ming dynasty China, the city faced many invasions from the Mongol Waci tribe. In 1476 (12th year of the Chenghua era), it was proposed that an Outer city be built outside of the then Beijing city. In 1553 (32nd year of the Jiajing era), a bigger rectangular Outer city wall and moat system was completed covering the south of the original Inner city wall and moat system, forming a situation similar to the "凸" character. This Inner city-Outer city wall and moat defence continued for nearly 400 years into the future.

After the takeover of Ming dynasty Beijing by the Manchus who also had their capital of their Qing dynasty in Beijing, the city's wall and moat defence system remained largely unchanged. However, the Ming Imperial city was completely redesigned. A great number of the residences of Ming dynasty inner cabinet officials were changed into commoner houses, also many imperial official's offices, servant's quarters, food and water storages, hay storages were changed into commoner houses as well. The Inner city residences became exclusively Eight Banner (Imperially related Manchus') households. While the Han Chinese were forced to live in the Outer city or outside the city. The Qing city planners also built many Imperial residences (for imperial relatives), and Gelug sect buddhist temples within the Inner city. They also built the "Three mounts Five gardens" greenery leisure complex in the western suburbs.

Dismantlement

During the Ming and Qing dynasties, the protection and renovation of the wall and moat systems of Beijing were extensive. No holes may be drilled, no arches made, and if any section has been damaged, even if missing just a single brick, were swiftly reported to the authorities and subsequently repaired [《大清会典》] .

According the historical records of the late Ming dynasty, when Li Zicheng retreated from the city of Beijing, not only did he order to set fire to the Ming Imperial palace complex, but also to the major city gates as well [《明史纪事本末》、《甲申传信录》] . But in 1960 when the walls were finally dismantled, the workers realised that both Dongzhimen and Chongwenmen towers and gate sections were the Ming originals《北京城垣的保护与拆除》,《北京规划建设》1999年第2期] . The fortifications of Beijing were kept well up until 1900. In 1900, when the Boxer Rebellion began. Zhengyangmen's gate tower was destroyed by fire by the Righteous Harmony Society, its watchtower was destroyed by fire by Indian troops; Chaoyangmen and Chongwenmen's watchtowers were destroyed by cannons by Japanese and British troops; Inner city's Northwest corner guard tower was destroyed by Russian cannon fire. At the same time, British troops brought down Yongdingmen's western section of the Outer city walls and the city walls surrounding the Temple of Heaven, moving the end of the Beijing-Fengtian railway (present Beijing-Shenyang railway) from the original that was outside of the city in Majiabao to inside the grounds of the Temple of Heaven where the British and American forces were headquartered. This was the first time since the Ming dynasty that the city walls of Beijing were opened. In 1901, British troops further brought down Yongdingmen's eastern section of the Outer city walls, further extending the end of the aforementioned railway eastwards until Zhengyangmen's eastern side, which will become the future Zhengyangmen East railway station (present Qianmen station), easing the retreat into the port city of Tientsin (present Tianjin) of British embassy and consulate nationals in the event of a need for retreat. Moreover, British troops also brought down south Dongbianmen's eastern section of the Outer city wall for the construction of the Beijing Dongbianmen-Tongzhou feeder railway.

The Imperial government of Qing China collapsed in 1911. Between 1912 and 1949, the Beiyang military government, the Republic of China Nationalist government, and the Northern China reform government all made minor deconstructions and adjustments. When the Beijing Circum-City railway was built in 1915, the Northeast and Southeast corner guard towers' enemy sight towers were dismantled, and the two side walls of both corner guard towers' two sides had arches built as passageways for trains; Dongshengmen's, Andingmen's, Chaoyangmen's and Dongzhimen's barbican and sluice gates were dismantled for the passage of trains. In addition, Zhengyangmen's barbican was dismantled as well to ease traffic in the Qianmen area. For the improvement of traffic, the city walls near Hepingmen, Jianguomen, Fuxingmen and several other minor gates had arches built as passageways for trains. Excepting the South to Southwest section, the Imperial city city walls were fully dismantled.

Due to negligence and lack of funding, Beijing's Inner city's and Outer city's major gates' gate towers, watchtowers, and corner towers were dismantled. Even so, by the time of the founding of the People's Republic of China in 1949, the majority of the moats and gate towers of Beijing remained, albeit in a dilapidated state.

In 1949 Beijing once again became the capital of the newly founded Communist government. Government-sponsored city-planning studies showed that the remaining Beijing wall and moat structures was a hindrance to traffic and future city expansion and development, and thus was proposed to dismantle them completely. The process of dismantlement took a long time. In the 1950s, the Outer city city walls was completely dismantled; The Inner city city walls began dismantling work in 1953. By the time of building the Beijing Metro system during the Cultural Revolution, the Inner city city walls had been completely dismantled.

At the time, there were great disagreement about whether to keep or to dismantle the city walls. Liang Sicheng was a leading advocate of the pro-keep supporters. He advocated making more arches in the city walls through which to pave new roads to serve increased traffic needs, and building a giant circum-city public park immediately hugging the city walls and moats to beautify the city's environment. In addition, the western sections of the city walls can help keeping the damage from the flooding of Yongding river at a minimum. Pro-keep supporters included Redologist Yu Pingbo, then Bureau of Culture Vice Minister Zheng Zhenfeng, as well as many Soviet city planners working on Beijing's city planning. But due to great political pressure in the contrary, the pro-keep's voice were much silenced《北京城垣的保护与拆除》,《北京规划建设》1999年第2期] . After the end of the Great Leap Forward, the 39,75 kilometres long Outer city city wall of Beijing had been completely dismantled, while the Inner city city wall was halved in perimeter length.

During the 1960s, the relations between China and the Soviet Union became bitter, and after the Sino-Soviet split, people felt that war with the Soviet Union was inevitable. Underground bomb shelters, underground "supply cities", and an underground railway (Beijing Metro) were commissioned. Work on the Beijing Metro began on the 1st of July, 1965. The technique of building the metro system at the time was open air digging and then building the "roof" afterwards. Thus, wherever the path of the underground metro goes, everything on the surface also had to be demolished. Taking into consideration that demolishing people's houses and relocating them to live elsewhere would be a much greater undertaking than to simply build the metro line where the original city wall and moat laid. It was thus decided that the metro line would be built under the foundations of the original city wall and moat system.

In the period between the beginnings of the city wall's dismantlement in 1950 and the big-scale dismantlement work that began in 1965, dismantlement work were under the supervision of Beijing city government's roads and development department. In addition, factories needing bricks and raw materials that the city's fortifications had, along with the common people volunteered in the slow dismantlement process. After construction began on the metro system, in order to increase the speed and efficiency of the dismantlement process before the metro construction workers arrive for the metro construction process, Railway soldiers' troops were brought into the dismantlement work. The first stage of the Metro Construction Project dismantled, the Inner city's southern city walls, Xuanwumen, and Chongwenmen, leaving behind a giant 23,6 kilometres long ditch in the south of the city to be used for the Metro; The second stage of the project began from Beijing train station in the southeast corner of the Inner city, passing through the original Jianguomen, Andingmen, Xizhimen and Fuxingmen sites, bringing down towers and walls along the way, leaving 16,04 kilometres of ditch space for the Metro. Out of that, an approximately 100 metres long section near Xibianmen was used by the metro construction workers a raw materials storage and therefore was spared dismantlement, although the northern sections were halved. The section from the east of Chongwenmen until the Inner city's Southeast corner guard tower were also spared dismantlement because the metro line makes a detour there towards the Beijing train station, although the tops of the walls where guards normally would walk were dismantled, leaving a wall on which it cannot be walked. Beginning in 1972, in order to pave the 2nd Ring Road on top of the Metro, as well as building high rise apartments and hotels in the Qianmen area, Beijing's eastern, southern, and western moats were covered over and became sewages.

By 1979, when the government ordered an end to the dismantlement of remaining city walls, and naming them cultural heritages, only Zhengyangmen's gate tower and watchtower, Deshengmen's watchtower, the Southeast corner guard tower, Inner city's northern moats, the section of the inner city city wall south of the Beijing train station, and a small section of Xibianmen's Inner city city wall remained intact. Thus was the end of the great majority of the Beijing fortification's history.

Defence

The defence system of Beijing during the Ming and Qing dynasties included city walls, moats, gate towers, barbicans, watchtowers, corner guard towers, enemy sight towers, and military encampments both outside and inside the city. These are also combined with the mountains immediately north of the city and the interior Great Wall sections on those mountain ranges.

During the Ming dynasty, the troops under permanent encampment in and around Beijing were called Jingjun or Jingying ("capital troops"). They were divided into Wujunying, Sanqianying, and Shenjiying. All of these began during the Yongle era《明史·兵志一》] . The three ying were further divided into 72 wei, named as Zhongjun (centre), Zuoyejun (left middle), Youyejun (right middle), Zuoshaojun ("left guard"), Youshaojun ("right guard"), these were collectively known as the Wujunying ("five troops")《明史·兵志一》] . The majority of the Jingjun were headquartered outside of west Deshengguan (originally Yuan Khanbaliq's Jiandemen site). some of the Jingjun troops camped in the rural districts of the Capital Area, in such areas as Nanyuan, Tongzhou, Lugouqiao, Changping, and Juyongguan interior Great Wall《明史·兵志一》] . After the Tumu Rebellion in the reign of Emperor Ying of the Ming dynasty, the entire Jingjun was destroyed, Yu Qian changed the grouping, bringing approximately 100,000 well-trained troops from several different camps into one supergroup, the 10-battalions supergroup. This was raised to 12-battalions during the reign of Emperor Xian of the Ming dynasty. These are commanded from within the Inner city in the Dongguanting and Xiguanting. Also building many drilling and training fields outside of the city walls that could be used as temporary encampments or troop drilling. The original Wujunying, sanqianyiing and Shenjiying were made into guards in charge of protecting the Imperial city and the Forbidden city. Later the Imperial guards were joined by the Jinyiwei and the Tengxiangwei whose commanders included "Mianyiwei Dahan General", "Hongkui General", "Mingjia General", "Bazong Director" and several other command posts. Forming a guard post in the Imperial city called "Hongpu". The city's gates were closed at night, and no one were allowed in or out unless special permission were given (one exception were carts that continually brought spring water from Mount Yuquan). At night, the streets of the city had guards on constant patrol, forbidding commoners' loud and disruptive behaviour, some streets had barricades to direct night traffic away. The city walls normally had no soldiers stationed, day or night, most live under the walls in encampments, leaving a few doing night shifts at gate towers, watchtowers, and enemy sight towers. Only when there is danger of enemy attacks do soldiers station themselves atop the city walls《明史·兵志一》] . During the mid-Ming times, there were constant sieges on Beijing from Mongol and HoujinManchu forces. Beijing was closed indefinitely many times, closing all the gates and forbidding commoners entrance into the city [《明史纪事本末》、《甲申传信录》] .

During the Qing dynasty, Beijing's defence forces mainly relied on the Xiaoqiying (or the Qiying), separately scattered in encampments within Beijing's Inner city, then mainly inhabited by Manchus: the Xianghuang banner within Andingmen, the Zhenghuang banner within Deshengmen, the Zhengbai banner within Dongzhimen, the Xiangbai banner within Chaoyangmen, the Zhenghong banner within Xizhimen, the Xianghong banner within Fuchengmen, the Zhenglan banner within Chongwenmen and the Xianglan banner within Xuanwumen. Each banner has an Office Hall, several troop barracks, patrol station and supply storage. Other than the Xiaoqiying, troops permanently encamped in and around Beijing included the Qianfengying, Hujunying, Bujun Xunbuying, Jianruiying, Huoqiying (in charge of artillery), Shenjiying (first began in the 11th year of the Xianfeng era), and the Huqiangying (in charge of guns)《光绪顺天府志·京师志八：兵制》] . From the Yongzheng era onwards, in the area around Yuanmingyuan and Xiangshan were camped the Eight banner guard troops in charge of protecting the imperial leisure parks《大清会典》] . The same system of eight banners is done with the nine gates of the Inner city, excepting the eight gates outside of Zhengyangmen. The troops consists of equally distributed Manchu, Mongol, Han soldiers. However the soldiers of the Chengmenling, who are in charge of protecting the city gates, come from other banners: Andingmen commanded by the Zhenglan banner, Deshengmen commanded by the Xianglan banner, Dongzhimen commanded by the Xiangbai banner, Xizhimen commanded by the Xianghong banner, Chaoyangmen commanded by the Zhengbai banner, Fuchengmen commanded by the Zhenghong banner, Chongwenmen commanded by the Xianghuang banner, Xuanwumen commanded by the Zhenghuang banner and Zhengyangmen's command post rotates between the eight. The Outer city's seven gates are commanded as follows: Xianghuang banner Han troops of Dongbianmen, Zhenghuang banner Han troops of Xibianmen, Zhengbai banner Han troops of Guangqumen, Zhenghong banner Han troops of Guang'anmen, Xianglan banner Han troops and Xiangbai banner Han troops both of Zuo'anmen, Xianghong banner Han troops of You'anmen and Zhenglan banner Han troops of Yongdingmen《大清会典》] . In the 6th year of the Yongzheng era, permanent barracks were built for the eight banners in the Inner city, excepting Zhengyangmen. Each gate had barracks of 460 rooms for a ying, 90 rooms for a ban, and 15 rooms for a geng, totaling 3,680 rooms. In addition, there were 16,000 rooms outside the city walls provided for the additional eight banners' soldiers, with each banner having 2,000 rooms, out of which 1,500 are allocated to Manchu troops, and 500 to Mongol troops. There were also 135 storages atop the Inner city city walls, 106 of which are provided for military direction flags, cannons, gunpowder and guns《大清会典》] . In the 10th year of the Qianlong era, 241 houses of 3 rooms each were added to the nine gates of the Inner city. The straw and earthen barracks constructed by the Outer city gates' troops were deteriorating, and thus 28 additional storages were added along with 3,616 Outer city barracks [《大清会典》、《光绪顺天府志·京师志八：兵制》] . During the Qing dynasty, the soldiers of the eight banners of the Xiaoqiying usually lived outside the city gates rather than on the city walls, this proved to be easier for the defence of the city in case of siege. Only when the emperor is leaving the city for Yuanmingyuan or the Temple of Heaven do the soldiers station themselves atop the city walls. An exception is Xuanwumen which is the only gate that stays open at night and thus has soldiers stationed atop the city walls continually. At noon, cannons fire atop Xuanwumen marking the time, (Xuanwumen literally means "Announcing Noon Gate")《光绪顺天府志·京师志八：兵制》] .

During the Ming and Qing dynasties, the main weapons used in the defence of the city were firelocks, cannons and bow and arrows. In 1629 (the 2nd year of the Chongzhen era), Houjin troops attacked Beijing, and in 17th year of the Chongzhen era, Li Zicheng's troops laid siege to Beijing，the Ming troops atop the city walls used cannons extensively during both sieges [《国榷》卷九十、《明季北略》卷五：崇祯二年十一月二十日，宣府总兵侯世禄、大同总兵满桂屯兵德胜门，与后金军交战，城上守军发炮助战，误中满桂所部将士，满桂本人也负伤，率残兵百余人退入德胜门瓮城。>《国榷》卷一百、《流寇长编》卷十七、《甲申纪事》：崇祯十七年三月十七、十八两日，李自成军冒雨猛攻北京内城，城上守军惧且怨，乃施放空炮，炮内未装铅子，借以敷衍塞责。] . During the Second Opium War in the Qing dynasty, the invading Beijing troops who are stationed outside the city walls gave up conquering Beijing city because it was too extensively protected, they then went on to burn down Yuanmingyuan and attack Haidian in the northwest and north of Beijing's suburbs.Between the 13th of August and 15th of August, 1900, when the Eight-Nation Alliance invaded Beijing, although unable to handle the overpowering troops of eight Alliance nations in the end, the fortifications nevertheless was able to withstand their cannon attacks for two full days. According to records from Alliance troops, the Qing forces fully utilised their advantage at a high point and in the protection behind Beijing's thick walls, shooting down at Alliance troops. Russian and Japanese forces attempted several times to use proxylin (guncotton) to explode a gap at Dongzhimen and Chaoyangmen, but failed because every time a soldier tried to light the fuse, that soldier was shot down [ [日] 佐原笃介《拳乱记闻》] 。Moreover, the barbicans, enemy sight towers, corner guard towers, were also utilised and proved to be quite effective at deterring enemy attacks, for example, the night of August the 13th, Russian troops had succeeded at invading Dongbianmen's watchtower, but suffered heavy casualties in the barbican, it wasn't until the late mornings of the 14th did they successfully conquer Dongbianmen's gate tower《瓦德西拳乱笔记》] . Even after the Outer city and Inner city fell to Alliance forces, the Imperial city's defenses still held. On the morning of August the 15th, American forces used several guns to try and destroy Tian'anmen's gates, but amazingly, the gates held. Instead, Japanese troops climbed the wall using ladders to open the gates and allow Alliance troops into the Imperial city《瓦德西拳乱笔记》] . In the "Guang'anmen Incident" that occurred on the 25th of July, 1937, a battalion of Japanese troops camped at Fengtai (a southern suburb of Beijing), declaring that they intended "to protect Japanese immigrants" and "to protect Dongjiaomin Street's Embassy district" used this as an excuse to move into Beiping (Beijing) city. When the unit's column of trucks began entering Guang'anmen, around twenty Chinese soldiers fired on them from atop the gate tower, forcing the Japanese battalion to abandon their entering the city. Showing that even in the modern warfare of the 1930s and 1940s, the dilapidated fortifications still had defensive usefulness.

Inner City

Beijing's inner city is also called Jingcheng ("capital city") or Dacheng ("big city"). The eastern and western sections were mostly remnants from Yuan's Khanbaliq, while the northern and southern sections were built during the early Ming dynasty in the Hongwu and Yongle eras. The walls were formed from rammed earth surrounded by rocks and followed by bricks on both the interior and the exterior. It had an average height of 12 to 15 metres. The northern and southern sections that were built in the early Ming were thicker than the eastern and western sections that were built in the Yuan dynasty, averaging 19 to 20 metres in thickness, and 16 metres in thickness at the top, forming a trapezoidal cross-section, with parapets at the top. The inner city had nine gates, and four corner towers at the four vertices. there were 3 sluice gates, 172 enemy sighting towers, 11.038 battlements. Immediately outside the city walls were deep moats 30 to 60 metres in width.

Inner City walls

The Inner city walls of Beijing had the city walls of Yuan's Khanbaliq as a foundation. In the first year of the Hongwu era, after the Ming troops entered Khanbaliq, General Xu Da directed Hua Jilong to build an additional city wall of rammed earth south of the original Khanbaliq's northern city walls《光绪顺天府志》京师志一·城池] . Later it was covered with stones and bricks, forming a second defense to the Khanbaliq original. In the 4th year of the Hongwu era, Khanbaliq's northern city walls were completely abandoned, dismantled and its materials used to reinforce (heighten and widen) the new northern wall a few kilometres south. Moreover, he ordered Zhang Huan to measure the original Yuan Khanbaliq Imperial city's perimeter, which amounted to 1.206 zhang (approximately 4.020 metres); he also ordered Ye Guozhen to measure the southern city's perimeter which amounted to 5.328 zhang (approximately 17.760 metres), the southern city was the remnants from the Jin Dynasty's capital Zhongdu.《光绪顺天府志》京师志一·城池] .

After the moving of the capital to Beijing in the 4th year of the Yongle era, the southern city walls were also moved south by 2 li (approximately 1 kilometre), however the original Khanbaliq city walls were not destroyed (excepting a small section which overlaps the planned future Ming Imperial city). Nevertheless, Khanbaliq's southern city walls were destroyed eventually by other factors, such as people looking for free bricks and stones. Khanbaliq's eastern and western walls remained. During the Yongle era, the southern, eastern and western walls were all reinforced with stones and bricks. In the first year of the Zhengtong era, Annamese (northern Vietnamese) Ruan(Nguyen) An was ordered to build the city's nine gate's gate towers, watchtowers, barbicans, sluice gates, and corner guard towers. In the fourth year of the Zhengtong era, the bridges leading into the gates were built. In the tenth year of the Zhengtong era, Zhu Yong was ordered to reinforce the interior walls of the city with bricks as well. Beijing's Inner city city wall and moat system was thus complete《光绪顺天府志》京师志一·城池] .

The Inner city city walls had a perimeter of 24 kilometres. It was roughly square, with the east and west walls slightly longer due to the north and south walls being moved from Yuan Khanbaliq's original positions. Also, the northwestern section lack a vertex; seen from a map it looks as if it has been bitten off. This is an allusion to the Chinese mythological story of Nüwa mending the heavens, in which "the heavens were missing in the northwest, and the earth was sinking in the southeast" [乾隆钦定《日下旧闻考》，卷十三] . However, according to scientific investigations done with remote sensing, this area originally had city walls built, but the area were mostly swamps and wetlands, and thus possibly was abandoned in favour of a diagonal connexion, placing this small triangle of an area outside of the city.

Throughout history, Beijing's Inner city came under siege many times, for example, Anda Khan's and Houjin's invasion during the Ming dynasty, the Boxer Rebellion and the Eight-Nations Alliance during the Qing dynasty, however they were all successfully defend against, with the notable exception of the Eight-Nations Alliance.

After the collapse of the Qing in 1911, in order to improve the city's traffic conditions and build a circum-city railway, Zhengyangmen's, Chaoyangmen's, Xuanwemen's Dongzhimen's and Andingmen's barbican, Dong'anmen, and the city walls of the Imperial city were all dismantled. In 1924, in addition to the nine original gates, Hepingmen was newly opened to allow traffic to pass which had only been a part of the Inner city city wall up until then. Many other gates such as the Qimingmen (present Jianguomen), Chang'anmen (present Fuxingmen) were opened, these two were actually archways rather than proper "men", as they didn't have a gate tower on top.

After 1949, the Communist Party of China ordered the dismantlement of the city walls on a giant scale. During the Korean War, in order to ease traffic density, 6 new archways were built: Dayabao alley archway , Beimencang archway (present Dongsi Shitiao archway), North Bell Tower Avenue archway, Xinjiekou archway, West Guanyuan archway and Songhe'an alley archway [《城记》，p309] .

After the 1950s, whether or not the dismantle the city walls of Beijing became a debated topic. Architect Liang Xicheng proposed to keep the city walls and convert it into a public park. In order to build the Beijing Metro system, nearly all of Beijing's Inner city city walls were torn down between 1965 and 1969. The eastern, southern and western sections of the moats of the Inner city were also covered over and became a part of the city's sewage system.

Inner City gates

Beijing's Inner city all have gate towers atop the city gates. These gate towers sit atop a rectangular platform at 12 to 13 metres of height on the city wall. They are closely attached to the surrounding city walls. Directly under the middle of platform is a giant archway, this is the "gate hole". Within this archway are two giant red wooden gates, opening outwards. On the exterior side of the gates are iron bulbs, while on the interior side gild copper bulbs are fitted. When the gates are closed, they are locked and reinforced in the behind with giant tree trunk sized wooden supports.

The Ming dynasty Inner city gate towers of Beijing were built during the Zhengtong era, each built in multi-eaved Xieshanding style. Grey tubed roof tiles are laid along with green glazed tiles. Excepting Zhengyangmen's gate tower which is 7 rooms in length and 5 rooms in width, others such as Chaoyangmen and Fuchengmen are all only 3 rooms in width. The detailed lay-out of the inner city gate towers are different from each other. Zhengyangmen's gate tower is the tallest and the most imposing of the inner city gate towers. Chongwenmen and Xuanwumen are slightly lower than Zhengyangmen. Dongzhimen and Xizhimen are even lower. But Deshengmen, Andingmen, Chaoyangmen, Fuchengmen are the lowest of the inner city gate towers built. Each of the inner city gate towers has 2 floors, one top one bottom, soldiers guarding the gate can climb up the floors to have a better view at sighting enemies.

Each of the Beijing's inner city gate towers has an additional watchtower directly in front of the gate tower. Each watchtower has a unique design, Zhengyangmen's watchtower is the most imposing of them all. The tower platform is raised at a height of approximately 12 metres, the tower structure is built in multi-eaved Xieshanding style, with grey tubed roof tiles and green glazed tiles at the top. The southern side has a length of 7 rooms, the northern side has a hugging side tower of 5 rooms in length. The eastern, western, and southern sides all have "arrow windows", openings of 4 rooms in length. The southern side has 52 such openings, the eastern and western sides each have 21 such openings. The tower structure is 38 metres in height, 52 metres in width, and 32 metres in walking depth, these specifications are the biggest among the inner city watchtowers. Of the 9 watchtowers accompanying the 9 gate towers of Beijing's inner city, Zhengyangmen's watchtower "Qianmen" is the only one with a gate directly under its tower structure, this gate under the watchtower is for the exclusive use of the emperor himself. The exterior designs of the other inner city watchtowers were similar to that of Qianmen, having a multi-eaved Xieshanding style gate tower in the front and a hugging side tower five rooms in width in the back. Under the eaves of the front are three rows of arrow windows, atop the eaves are still another row of arrow windows.

On both sides of a watchtower are also walls, these walls are connected to either the inner walls or the outer walls. Thus, the area nearby a gate are formed into a concave miniature city, this is called an barbican. The cross-section of a barbican is square in shape in such barbicans as that of Dongzhimen or Xizhimen; rectangular in shape as the ones at Zhengyangmen or Deshengmen; and semicircular such as the ones at Dongbianmen and Xibianmen. However most of the inner city barbicans were square in shape, but they did not have 90° vertices, rather they had arcs instead which made it more difficult to climb or destroy.

Each of the inner city barbicans had its own unique designs. The gates of the inner city barbicans ope towards the city, that is, the gates of the barbican of the northeastern Dongzhimen opens towards the south, while the gates of the barbican of the southeastern Chaoyangmen opens towards the north. This aids in moving troops from one city gate to another through the outside of the city walls more efficiently. This is the same with the barbicans of Xizhimen and Fuchengmen of the western walls, as with those of Chongwenmen, Xuanwumen of the southern walls. The central gate, Zhengyangmen, has gates on three sides, the southern, the eastern and the western. Only the barbicans of Deshengmen and Andingmen of the northern walls are exceptions, which have gates opening towards the east.

Zhengyangmen

Zhengyangmen is located at the centre of the Beijing Inner city's southern city walls. It was completed in the 17th year of the Yongle era. It was originally called by the name of the Yuan Khanbaliq's southern wall's middle gate's name --- Lijiangmen, it was however changed to its present name during the Zhengtong era. Zhengyangmen's gate tower is located at a height of 13,2 metres on the platform atop the city wall. there are two stories of 27,76 metres in height. 7 exterior rooms of 41 metres in width and 3 interiors rooms of 21 metres in width. It is built in the triple-eaved Xieshanding style, with green glazed tiles. In the middle of the platform is an archway, inside the archway is a thousand jin (approximately 500 kilograms) lock. Directly south is the watchtower, commonly known as "Qianmen", it is also 7 rooms wide. There are hugging side towers in the rear, the upper floors of which have 4 arrow windows on the southern sides, each floor having 13, the 8 other inner city watchtowers all have 12 arrow windows on each floor. The eastern and western sides have 4 floors fitted with 4 arrow windows on each floor. The watchtowers and the gate towers are connected with thick brick walls, the surrounding area forms the Zhengyangmen barbican, a miniature barricaded city 108 metres in width, 85 metres deep, the eastern and western sides have side gates with arches underneath, fitted with thousand jin locks. Normally, the watchtower gate and the eastern side gate are closed, commoners use the arch underneath the western side gate.

Zhengyangmen's watchtower was partially burnt in 1900 by Boxers during the Boxer Rebellion when they burnt down , the rest of the tower structure that remained intact was used as firewood by the Indian soldiers under British command in the cold winter of that year. The gate structure was eventually reconstructed in the late years of the Qing dynasty. To ease the traffic, the Zhengyangmen barbican was ordered dismantlement in 1915 by Beiyang military government's Internal Affairs minister Zhu Qiling. The watchtower and the gate tower were saved from dismantlement in 1965 on the orders of the then premier Zhou Enlai.

*The inner city barbicans all had a temple built within its grounds, and the barbican of Zhengyangmen had two. Guandimiao in the west and Guanyinmiao in the east. The statues within Guandimiao were all Ming originals, every time the Qing emperor came back from a visit to the Temple of Heaven, he would always go to Guandimiao to light some incense. There are "three treasures" in Guandimiao, they are a precious sword, a Guandi painting, and a horse statue made of white jade. During the Cultural Revolution, the temple structures of Guandimiao and Guanyinmiao were dismantled.

Chongwenmen

Chongwenmen is located on the inner city southern wall's eastern section, it is commonly called "Hademen". Built in the 17th year of the Yongle era, and before the Zhengtong era it was called "Wenmingmen", which was the original name used during the Yuan dynasty. After the Zhengtong era, a name was taken from «Zuozhuan»'s excerpt, "崇文德也"("chong wen" de ye). It was also during the Zhengtong era that the gate had barbican, sluice gates and a watchtower built.

Chongwenmen's gate tower has a width of 5 rooms on the northern and southern sides of 39,1 metres, a walking depth of 3 rooms of 24,3 metres, the gate tower has two floors, the tower platform is at a height of 35,5 metres. The tower structure is built in multi-eaved Xieshanding style, grey and green glazed tiles. Its watchtower design is similar to that of Zhengyangmen's, only on a slightly smaller scale. The exceinte has a width of 78 metres, a depth of 86 metres, there are sluice gates on the western side, along with arches. Chongwenmen also has a Guandimiao in the northeastern corner, built facing the south. In 1900, Chongwenmen's gate tower was destroyed by British cannon fire during the Boxer Rebellion, and completely dismantled in 1920. In 1950, Chongwenmen's barbican was dismantled. In 1966 Chongwenmen's gate tower was dismantled.

*Chongwenmen is a "Sighting gate", it has the innate connotation of "a bright and prosper future". Its symbol is the Chongwen iron turtle. Due to its close proximity to the busy Tonghui river, Chongwenmen is also the busiest gate of all the city gates of Beijing. There were city entry and departure taxes at Chongwenmen throughout the Ming dynasty, Qing dynasty, and early Republican China eras. The Empress Dowager Cixi's "cosmetic spending" and early Republican China president's annual salary all came directly from the taxes taxed at Chongwenmen. In 1924, Feng Tianxiang started a coup in Beijing, after that, the taxation at chongwenmen was stopped.

*Every day when the gates are closed, only Chongwenmen has bells announcing the closing to those wishing to enter or leave the city. The other gates use a flat instrument to announce the closing, it produces a "tang" sound, thus the Old Beijing city has the saying of "nine gates, eight "tang"s, one old bell". This is also a possible etymological origin of the "zhongdian" to refer to the "hour" in the Beijing dialect. In the past there were many spirit distilleries in the southern Daxing suburbs of Beijing, many carts carrying newly brewed spirits go through Chongwenmen, this is the basis of the saying, "Chongwenmen has carts carrying spirits entering, Xuanwumen has carts carrying prisoners leaving".

*When Chongwenmen was dismantled during the Cultural Revolution, the workers discovered that the gate was the original Ming structure, using "phoebe puwennensis" wood. Some of the remaining wood materials were used in the Forbidden City and Tian'anmen reconstructions.

Xuanwumen

Xuanwumen is located on the southern wall's western section. It was built in the 17th year of the Yongle era when Beijing's southern walls were expanded. Before the Zhengtong era the gate continued to use the original Yuan gate name of Shunchengmen, while it was referred to as Shunzhimen by the commoners. During the Zhengtong era, the gate tower was completely rebuilt, a barbican, a sluice gate tower, and a watchtower were also added. Taking the new name "Xuanwu (martial announcement)" from Zhang Heng's «Dongjing Fu» quote, "the martial etiquette is to announce 武节是宣wu jie shi xuan". Xuanwumen's gate tower is five rooms in length on the faces (32,6 m), three rooms in width on the sides (23 m), two floors high (33 m). The roof is built in multi-eaved Xieshanding style with green glazed tile edges on grey tiles. Xuanwumen's watchtower is similar to Zhengyangmen's watchtower, only on a slightly smaller scale. The barbican is 75 metres wide and 83 metres deep, with sluice gates on the eastern and western sides, as well as two respective archways. Xuanwumen's Guandi Temple is locate on the northwestern corner of the barbican, it faces southwards. The watchtower was dismantled in 1927, the watchtower platform and the barbican were dismantled in 1930, and the gate tower was dismantled in 1965.
*Xuanwumen is informally referred to as the "Death Gate", this is because carts carrying prisoners awaiting execution through Xuanwumen. The reason for this was that Beijing's many cemeteries were located in and around Taoranting in the southern suburbs, while the place of execution was located in Caishikou, also in the south, therefore the condemned going to their executions have to leave the city through Xuanwumen. Besides prisoners, commoners who had died would often leave the city in funeral carts through Xuanwumen to the cemeteries in the south of the city. There are giant cannons on Xuanwumen which are fired at the noon hour.
*Of the nine inner city gates of Beijing, Xuanwumen is built on the lowest sea-levels. Although normally the river system is built to accommodate and direct water flow out of the city through Zhengyangmen's eastern sluice gates, these proved ineffective during heavy rainstorms, when most of the water would flood out of Xuanwumen. According to «Guangxu Shuntianfu Zhi»'s record, during the 34th year of the Kangxi era, there were heavy rainstorms in Beijing, the rainwater flooded Xuanwumen's gates, making it impossible to open the gates, in the end, 6 elephants were brought over from the zoo to force open the gates, finally dissipating the flood out of the city.

Dongzhimen

Dongzhimen is located on the inner city eastern wall northern section. It is built on the location of Yuan Khanbaliq's Chongrenmen. During the 17th year of the Yongle era, quoting "东方盛德属木、为春"'s and "直东方也，春也"'s meaning, changing the name of the gate to its modern name [《城记》，p300] . Dongzhimen's gate tower is five rooms in length (31,5 m), three rooms in width (15,3 m), two floors (34 m). Built in multi-eaved Xieshanding style, grey tiles with green glazed edges. Its watchtower is similar to Zhengyangmen's watchtower, except built on a smaller scale. The barbican was built during the final years of the Yuan dynasty, because the gate during the Yuan when it was called Chongrenmen, was Yuan Khanbaliq's eastern city wall's central gate, located at the midpoint, thus the barbican is nearly square-shaped, the northern and southern walls being 68 metres in length, and the eastern and western walls being 62 metres in length. There are archways and sluice gates on the eastern and western sides. Dongzhimen's Guandi Temple is located on the northeast corner, facing southwards. The sluice gate towers and the barbican were dismantled in 1915 when the circum-city railway was built. The watchtower was dismantled in 1930. The watchtower platform was dismantled in 1958. The gate tower was dismantled in 1965.
*Dongzhimen has a treasure outside its gates, a whole pagoda made completely from iron. The iron pagoda has a stone statue of Yaowangye. Many carts carrying raw wood supplies enter the city through Dongzhimen.
*Dongzhimen's barbican is the smallest in scale of the nine inner city gates of Beijing, this was why its Guandi temple had no proper statue of Guandi, being replaced by a minor deity made of wood. Thus giving rise to the old Beijing saying of "Nine gates ten temples, one without morality".

Chaoyangmen

Chaoyangmen is located at the inner city eastern wall's midpoint. It was located on Yuan Khanbaliq's Qihuamen. After the name was changed to Chaoyangmen, it was still informally known by its Yuan name Qihuamen by the commoners. Chaoyangmen's gate tower and watchtower are both similar to Chongwenmen's, its gate tower is 31,35 metres wide, 19,2 metres deep, 32 metres high. The barbican is 68 metres wide, 62 metres deep, with a sluice gate and an archway on the northern side. Its Guandi temple is located on the northeastern corner, facing southwards. The watchtower was destroyed by Japanese forces in 1900, it was rebuilt in 1903. The barbican was dismantled in 1915 when the circum-city railway was built. The gate tower and its platform were dismantled in 1953. The watchtower was dismantled in 1958.
*Chaoyangmen is Beijing's "Food Gate", through which many carts carrying staple foods enter the city. The reason is that this gate is the closest to the Beijing-Hangzhou Grand Canal, staple food such as wheat and rice from the south China plains enter the capital through this gate, much of it stored within the storages just inside Chaoyangmen. Thus it has the symbol of a wheat grain engraved on the barbican gate's archway. Chaoyangmen also has the informal name of "Dumen", having the meaning of a "杜门resting station".

Xizhimen

Xizhimen is located on the inner city western wall's northern section. Built on the site of Yuan Khanbaliq's Heyimen. During the 17th year of the Yongle era it was changed to its current name from its western location (Xizhimen=western axis gate). Xizhimen's gate tower and watchtower is similar to that of Dongzhimen, its gate tower is 32 metres long, 15,6 metres wide, 32,75 metres high. Its barbican is 68 metres by 62 metres, with a sluice gate and an archway on its southern side. Its Guandi temple is located on the northeastern corner, facing southwards, which was dismantled in 1930. Xizhimen was Beijing's last gate to remain fully intact. Nevertheless it was still completely dismantled in 1969. During the dismantlement process, it was discovered that part of the barbican gate's archway were the Yuan Khanbaliq Heyimen originals from the 13th century.
*Due to the poor condition of the water supply within Beijing city, the imperial family and wealthy families would get all of their water from the springs on Mount Yuquan in the northwestern suburbs. Every morning, carts carrying spring water from Yuquanshan would enter the city through Xizhimen. Thus, a symbol of water waves is engraved on the barbican gate archway of Xizhimen.
*Heyimen's barbican was built during the reign of Yuan Shundi, in the 19th year of the Zhizheng era, it use was continued for over 60 years during the Ming dynasty, when during the Zhengtong era, when the other inner city gates were all undergoing complete reconstruction, it was also covered over with bricks thus merging with Ming's new watchtower platform.

Fuchengmen

Fuchengmen is located at the inner city western wall's midpoint. Its original site was Yuan Khanbaliq's Pingzemen. It was still informally known as Pingzemen by the commoners even after its name changed to Fuchengmen. It was mended during the 14th year of the Hongwu era of the early Ming dynasty, completely rebuilt during the 1st year of the Zhengtong era. Taking its new name "Fucheng" from the classic «Shangshu»'s "六卿分职各率其属，以成九牧，阜成兆民". Its gate tower and watchtower are similar to Chaoyangmen's, its gate tower is 31,2 metres by 16 metres and 30 metres high. Its barbican is 74 metres by 65 metres, with a sluice gate and an archway on its northern side. Its Guandi temple is located on the barbican's northeastern corner, facing south. The sluice gate tower and watchtower were dismantled in 1935. Its barbican and watchtower platform were dismantled in 1953. Its gate tower was dismantled in 1965.
*Due to its proximity to Xishan, while Xishan Mentougou's coal reserves are crucial to warming Beijing's homes during the winter, thus many carts carrying coals would enter the city through Fuchengmen. Fuchengmen's barbican gate's archway has the symbol of a plum flower engraved (plum flower "梅Mei" and coal "煤Mei" are homophones in Chinese, one is not as ugly as an engraved symbol as the other, while the plum trees planted near Fuchengmen blossoms around the time when coal carts stop going to and fro Fuchengmen when spring arrives). This gives rise to the old Beijing saying of "Fucheng's plum blossoms announces the arrival of the new spring's warmth". Fuchengmen is also informally referred to as "惊门Jingmen", having the meaning of "Justice".

Deshengmen

Deshengmen is located on the inner city northern wall's western section. Its name was changed from Yuan Khanbaliq's "Jiandemen" to "Deshengmen" during the early Ming dynasty, having the implied meaning that the Ming won the war against the Yuan Mongols by having strong ethics and morals. During the 4th year of the Hongwu era, Beijing's northern city walls were rebuilt slightly south from the Yuan's northern walls. Its gate tower is 31,5 metres by 16,8 metres, with a height of 36 metres. Its barbican is 70 metres by 118 metres, its scale among the nine inner city gates being only second greatest to that of Zhengyangmen. The barbicans western side has a sluice gate and an archway. Its Zhenwu temple is located at the midpoint of the northern side of the barbican, south facing. In 1915, the barbican was dismantled. In 1921, the gate tower was dismantled. In 1955, the gate tower's platform was dismantled. Deshengmen's barbican's northern and southern axis are extra wide (118 m), thus it wasn't necessary to dismantled them when Beijing's metro system was built. In 1979, it was proposed that the watchtower be dismantled, however later it was kept intact.
*Both the Ming and the Qing, after defeating the Yuan and the Ming respectively entered the city for the first time through Deshengmen, and thus the name "Desheng" meaning "morally victorious". Thus many carts carrying weapons use this gate to enter and leave the city for luck. Deshengmen is also informally known as "修门Xiumen", meaning "having high moral and ethical standards".

Andingmen

Andingmen is located on the inner city northern wall's western side. It was built when Yuan Khanbaliq's Anzhenmen was moved south during the early Ming dynasty, subsequently renamed Andingmen, having the meaning of "peace and tranquility under the heavens". Its gate tower is 31 metres by 16,05 metres, and 36 metres in height. It barbican is 68 metres by 62 metres, with a sluice gate and an archway on its western side. The barbican was dismantled in 1915. Its gate tower and watchtower were dismantled in 1969.
*Seven out of nine of Beijing's inner city gates all have a Guandi temple built within its barbican grounds, only Andingmen and Deshengmen have Zhenwu temples instead, this is because both Andingmen and Deshengmen are used by soldiers entering and leaving the city, possibly for the battlefields.
*Andingmen is also informally known as "生门Shengmen" having the meaning of "bountiful harvest", this is why the Emperor always uses this gate when leaving the city for the Temple of Earth, praying for a bountiful harvest. Outside Andingmen are many feces storages to be used for fertiliser, thus many carts carrying feces leave this gate for the farmlands in the countryside.
*During the dismantlement process, a small experiment to test the structural integrity of its gate tower was conducted. It was found that the gate tower structure could lean forward by 15 degrees and still withstand collapsing.

Newly opened archways

*Shuiguanmen is located near Zhengyangmen's eastern sluice gate, in 1905 the District Works Office of the Dongjiao Embassy District covered the original moat water system over with plates of concrete, and also opening a new archway in place of the original sluice gate, thus forming a new gate. This new gate could be used as a means of swiftly retreating to the Zhengyangmen railroad station. Two iron gates were attached to the gate's archway, the two sides of the archway has one hollowed-out room on each side serving as guard stations.

*Hepingmen is located at the inner city southern walls, between Zhengyangmen and Xuanwumen. It was opened in 1926 to ease the traffic congestion of the area. There aren't a gate tower for this gate, nor a barbican, there are only two holes drilled from the wall serving as passageways in and out of the city. When the holes were drilled, Its surroundings were made thicker and wider than before for reinforcement. It was originally named "Xinhuamen", however it was changed to "Hepingmen" in 1927 to distinguish it from the famous Xinhuamen, which is the entrance to Zhongnanhai, a complex of central governmental offices. The archway are 13 metres high and 10 metres wide each, having two iron gates attached as well. In 1958, the top of the archway was dismantled, and instead became a simple opening in the inner city walls.

*Jianguomen is located at the southern edge of Beijing's inner city's eastern walls, it is at the northeast region of the Beijing Ancient Observatory. The walls in this area were dismantled in 1939 by the puppet Beijing provisional government, and in its place an opening 7,9 metres wide was opened. It was in the shape of an inverted "八" character. Although it is an opening and not an archway or gate, it was nevertheless given the name of a gate --- "Qimingmen". The name was changed to "Jianguomen" in 1945. In 1957 it was torn down along with the surrounding inner city walls.

*Fuxingmen is located at the southern edge of Beijing inner city's western walls, it is at the same latitude of Jianguomen on the eastern walls. The walls in this area were dismantled in 1939 by the puppet Beijing provisional government, and in its place an opening 7,4 metres wide was opened. It was in the shape of an inverted "八" character similar to Jianguomen. Although it is an opening and not an archway or gate, it was nevertheless given the name of a gate --- "Chang'anmen". The name was changed to "Fuxingmen" in 1945, but unlike Jianguomen which hasn't a gate tower platform, a 12,6 metres high platform was built and a single-arch passageway 10 metres in width was added. the complete structure was dismantled in 1955.

Inner City corner guard towers

There are four corner guard towers located at the four vertices of Beijing's inner city walls. They are all similarly designed, multi-eaved Xieshanding style having grey tiles with green glazed edges, its cross-section is curvy zig-zag shaped. The tower alone has a height of 17 metres, adding the height of the platform, its height is around 29 metres to the ground. the two adjacent sides facing out of the city are 35 metres in width respectively, each having four floors fitted with arrow windows, with 14 arrow windows on each floor. The two adjacent sides facing into the city also have four floors fitted with arrow windows respectively, but with only four arrow windows on each floor. These two sides facing into the city also have big openings square in shape with reinforced wooden windows serving as true windows that are normally open for air and light to pass through, while those on the sides facing out of the city are normally closed, and only opened when shooting arrows or cannonballs. The interior of the towers are hollow with no floor board, there are only floor boards immediately hugging the four sides of the towers and connected to the stairs.

Of the four corner guard towers of Beijing's inner city, only the southeastern one survived intact, this was due to its proximity to Beijing's main train station located also in the southeast, when the metro was built, it was thought that building the metro so close to the train station would disrupt the important railroad services into the capital city, and thus a new metro route around the north of the train station was used, therefore sparing the dismantlement of the southeastern corner guard tower and the sections of the inner city walls surrounding the corner guard tower. Of the other three corner guard towers, the northeastern one was dismantled in 1920, and its platform later in 1953; The northwestern corner guard tower was destroyed by Russian cannonfire in 1900 during the Boxer Rebellion, its platform was dismantled later in 1969; The southwestern corner guard tower was dismantled in 1930 because there weren't enough funds for its periodic repair, its platform was dismantled in 1969.

Outer City

In 1553, the 32nd year of the Jiajing era, the outer city was expanded. It is also called "Guocheng" or "Waiguo". Its walls are 28 kilometres in perimeter, 7,5 to 8 metres high, with 12 metres of width at the bottom and 9 metres at the top. Its southeastern corner was built without a vertex to avoid the low swamps in the area, thus fulfilling the legend of when Nüwa was mending the heavens, heaven's northwest was missing and Earth's southeast was sinking.

In the 28th year of the Jiajing era, when the expansion of the outer city was planned, it was originally conceived that smaller box-shaped "minor cities" would be built around the city gates, forming nine smaller boxed minor cities around the nine inner city gates surrounding the inner city, which would be a formidable defense addition to the city. Instead, it was changed later to a second even larger city south of the inner city. Its southern walls encompasses the southern walls of the Temple of Heaven, its eastern and western walls then extend north until becoming parallel with the inner city's eastern and western walls, about 2 kilometres away from touching the inner city walls, this was where the Yuan Khanbaliq's original rammed earth city's eastern and western walls' southern sections laid before being abandoned in the closing years of the Hongwu era during the early Ming dynasty. Dismantling the rammed earth structure of Yuan and taking some of the raw materials, the expanded outer city's northern wall's northeastern and northwestern sections were built, both ending where the inner city's southern walls began. The outer city walls have a perimeter of approximately 60 kilometres, forming a "凸"-character-shaped relationship with the inner city walls. 11 gates were built, 3 each on the eastern, southern, and western walls, and 2 on the northern walls (1 on the northeastern section and 1 on the northwestern section).

In 1550, the 29th years of the Jiajing era, construction began on 3 outer city box-shaped "minor cities", however because of their proximity to inner city gates, where many commoner's houses and shops have sprung up, many buildings needed to be dismantled, the disgruntled commoners forced the abandonment of the project not long after the construction began. In 1553, the 32nd year of the Jiajing era, it was decided that the rest of Yuan Khanbaliq's rammed earthen walls would be dismantled and its raw materials used to complete the outer city walls, eventually forming a "回"-character-shaped relationship with the inner city walls. The plan was to extend the outer city walls to have a perimeter of 70 kilometres, the east and west 17 kilometres, and the north and south 18 kilometres, adding 11 more gates, 176 more enemy sight towers, 2 additional sluice gates outside of Xizhimen and Tonghui River respectively, and 8 more sluice gates at other low swampy areas. The outer city expansion was a grand project greater than any of the capitals of the previous Chinese dynasties, under Yan Song advice, the project was divided into segments, with the southern walls built first, thus adding extra defense to the bustling commercial district south of inner city's Zhengyangmen. The Emperor approved, construction began on the 32nd year of the Jiajing era's 3rd lunar month (it was a leap lunar month), work was finished in the same year's 10th lunar month. The eastern and western walls were planned in the second segment of the project, however due to successive invasions from the Mongols and Manchus, much of the soldiers were brought to the northern frontiers to defend the Great Wall, and thus few could be used for the construction. Moreover, in 1557, a great section of the Forbidden city caught on fire, much of the workers and funds poured into the reconstruction of the palaces. The expansion of the outer city walls was thus never completed. In 1564, the outer city gate's barbicans were built.

Outer City walls

Beijing's outer city has a perimeter of 28 li's or 14,409kilometres, it is wide on the east-west horizontal axis, and narrow on the north-south vertical axis. 4 corner guard towers are built on the four corner vertices, along with 7 gate towers. The wall's exterior have bricks averaging 1 metre in width, mostly large bricks from the Ming dynasty, the interior averages 0,7 metres, mostly small bricks from the Qing dynasty. The outer city walls have an average height of 6 to 7 metres, its top has an average thickness of 10 to 11 metres, its base has an average thickness of 11 to 15 metres. The western sections of the outer city walls are the most narrow, averaging only 4,5 metres at the top and 7,8 metres at the base.

The outer city walls, gate towers and corner guard towers were dismantled between 1951 and 1958.

Outer City gates

Beijing's outer city has 7 gates, 3 on the southern walls, 1 each on the eastern and western walls, lastly there are also two side gates on the northern walls (on the northeastern and northwestern sections respectively). The outer city gate towers are all smaller in scale than the inner city's gate towers. The grandest in scale is the one lying on the north-south axis of the city, directly south of Forbidden city's Wumen, Imperial city's Tian'anmen and Inner city's Zhengyangmen --- outer city's central southern gate Yongdingmen. Yongdingmen has a gate tower of approximately 20 metres in height, multi-eaved Xieshanding style, 7 rooms by 3 rooms. Just below Yongdingmen's scale is Guangningmen (present-day Guang'anmen), it is only slightly lower in height than Yongdingmen. Guangqumen's, Zuo'anmen's, You'anmen's gate towers are all single-eaved Xieshanding style with only one floor, their heights only a mere 15 metres. The two side gates, Dongbianmen and Xibianmen are even smaller in scale.

The outer city gate had only their barbicans outside of the gate towers during the Ming dynasty. The watchtowers were only built during Qing dynasty's Qianlong era. The watch towers of the outer city are also smaller in scale when compared with the inner city equivalents. Yongdingmen's watchtower is the grandest in scale among the outer city gates' watchtowers, it has two rows of arrow windows with 7 windows in each row. The left and right sides have 2 rows of 3 windows each respectively, amounting to 26 windows in total. There isn't a side tower hugging the interior of the watchtower as with the inner city gates' watchtowers, there is only an archway. Guang'anmen's, Guangqumen's, Zuo'anmen's, and You'anmen's four watchtowers are even smaller in scale, having only 22 windows in each. Dongbianmen's and Xibianmen's watchtowers are the smallest in scale, having only 8 windows. Different from the inner city's barbicans, the outer city's barbicans are all built around the base of the watchtower instead of the base of the gate tower, thus forming a straight line with the gate's archway. There aren't any Guandi Temples built in the barbicans of the outer city gates.

Yongdingmen

It is located on the southern wall's midsection. It was built in the 31st year of the Qianlong era of the Qing dynasty in 1766 imitating the style of the inner city gates, multi-eaved Xieshanding style, grey tiles with glazed green rims, two floors, 26 metres in height, 5 rooms by 3 rooms, 24 metres by 10,5 metres. Its watchtower is small in scale, 3 rooms by 1 room, 12,8 metres by 6,7 metres, single-eaved Xieshanding style with grey roof tiles. Two levels of arrow windows, 7 windows on each level on the southern face and 3 windows on each level on the eastern and western sides. Directly under the platform of the watchtower's platform is a single archway. It has a rectangular-shaped barbican, 42 metres wide from east to west, and 36 metres wide from north to south. It has curved edges instead of 90 degree vertices at the corners. Its barbican was dismantled in 1950, its gate tower and watchtower were dismantled in 1957. In 2004, the gate tower was reconstructed slightly north of the original location.

Zuo'anmen

It is located on the southern wall's eastern section. The gate tower is built in single floored single-eaved Xieshanding style with grey roof tiles. It is 3 rooms by 1 room, 16 metres by 9 metres, the gate tower is 6,5 metres in height, adding to that of the platform it is 15 metres high. The watchtower is also single floored single-eaved Xieshanding styled with grey roof tiles. It is 3 rooms by 1 room, 13 metres by 6 metres, 7,1 metres high. Its arrow window arrangement and barbican specifications are the same as that of Yongdingmen's. The gate tower and watchtower were dismantled in the 1930s, its gate tower platform, watchtower platform and barbican were dismantled in 1953.
*Zuo'anmen is commonly referred to as "Jiangcamen". "江擦（jiāng cā）" is "礓磋（jiāng cuō）" under sound change, while having the same meaning. In traditional Chinese architecture fields, "礓磋（jiāng cuō）" also called "礓礤 (jiāng cǎ)" are stone steps without ladder like step platforms.

You'anmen

It is located on the southern wall's western section. It is commonly known as "Fengyimen" or "Xinanmen" ("southwestern gate"), this is because Jīn dynasty's Zhongdu("central capital"), its Fengyimen was built nearby. All of its specifications are the same as that of Zuo'anmen. In 1956, its barbican and watchtower were dismantled, in 1958 its gate tower was dismantled.

Guangqumen

It is located slightly north of the eastern wall's midsection. Its common name is "Shawomen". It has the same specifications as Zuo'anmen. During the 1930s the watchtower was dismantled, in 1953 the barbican and gate tower were dismantled.
*During the 2nd year of the Chongzhen era of the final years of the Ming dynasty, Ming general Yuan Chonghuan defeated Manchu's Houjin dynasty forces at this gate. In 1900, when the Eight Nation alliance forces reached Beijing, they did not attack this gate at first, thus much of the troops guarding the gate were moved to aid in the defense of the other outer city gates, British troops took this opportunity to defeat this gate, then bombarding the inner city's Chongwenmen from the Temple of Heaven, thus entering the inner city.

Guang'anmen

It is located slightly north of the western wall's midsection. It was called "Guangningmen" during the Ming dynasty, also called "Zhangyimen" then (being on the same axis as that of Zhangyimen of Jin dynasty's Zhongdu). During the Qing dynasty, in order to avoid criticism toward Qing's Emperor Xuan, who was named Minning (旻宁), the name was changed from "Guangningmen" to "Guang'anmen". Its original specifications were the same as that of Guangqumen. Due to its heavy use by new arrivals entering the city from the southern Chinese provinces, Emperor Qianlong decided to expand the scale of this gate to make it more impressive and majestic. Imitating Yongdingmen and the inner city gates, Guang'anmen was expanded in the 31st year of the Qianlong era. Its gate tower was built in two floored multi-eaved Xieshanding style, grey roof tiles with glazed green rims. 26 metres high, 13,8 metres by 6 metres, 3 rooms by 1 room. The barbican was originally semi-circular-shaped, after Qianlong's expansion, it became rectangular-shaped with curved edges, 39 metres by 34 metres. Its barbican and watchtower were dismantled in the 1940s, its gate tower was dismantled in 1957.

Dongbianmen

It is located at the northeastern corner of the outer city walls. When the outer city was built during the Jiajing era, the funds ran short, and thus the eastern and western walls building northwards were stopped short, and instead turned towards the edges of the inner city's southern walls. A corner guard tower was built at the northeastern and northwestern corners, as well as two temporary side gates, the northeastern one became Dongbianmen ("eastern side gate"), the northwestern one became Xibianmen ("western side gate"). at first these were only temporary and thus were not named, it was only 10 years after its completion that it was named. Its gate tower has similar specifications as Zuo'anmen's, only on a slightly smaller scale. 11,2 metres by 5,5 metres, 12,2 metres high. There isn't an archway under the gate tower, instead a smaller wooden side gate was built on the side. The watchtower was built during the Qianlong era, with two levels of arrow windows, 4 windows per level on the northern side, and 2 windows per level each on the eastern and western sides. Its barbican and watchtower were dismantled in the 1930s due to lack of funds for their repair work. Its gate tower was dismantled in 1958 when Beijing's main train station was built.

Xibianmen

It is located at the northwestern corner of the outer city walls. It has a height of 10,5 metres, and the other specifications are the same as that of Dongbianmen. It was dismantled in 1952. Parts of the barbican walls remain.

Corner guard towers

There are four corner guard towers at the four vertices of the outer city walls. They were built in the 32nd year of the Jiajing era, and are all built in single floored single-eaved Xieshanding cross (square-shaped) style. Approximately 7,5 metres high, 1 room by 1 room, 6 metres by 6 metres. Two levels of arrow windows, the two sides facing out of the city have 3 windows on each level, and the two sides facing towards the city have 2 windows on each level. The southwestern and northeastern corner guard towers were dismantled in the 1930s, the southeastern and northwestern corner guard towers were dismantled in 1955 and 1957 respectively.

Imperial City

Beijing's Imperial city was built during the Yongle era. It was expanded northwards, eastwards and southwards from the foundations of Yuan Khanbaliq's imperial city, it can be considered as an expansion of the Palace city (Forbidden city), solely for the use of the imperial family. It is rectangular in shape with a vertex missing in the southwestern corner due to the construction of Qingshou Temple. The average height for the walls is approximately 7 to 8 metres, 2 metres of thickness at the base and 1,7 metres at the top. It is painted red on the exterior, with glazed imperial yellow tiles at the top. It has a perimeter of 9 kilometres (north: 2.506 metres, south: 1.701 metres, east: 2.756 metres, west: 3.724 metres). There are 7 gates (other sources count 4, 6 or 8 gates) [北京皇城六门之说常见于明朝，当时以大明门为皇城正门，承天之门为宫城外门，因此皇城城门包括大明门（大清门）、长安左门、长安右门、东安门、西安门和厚载门（地安门）；七门之说常见于清朝，包括大清门、长安左门、长安右门、天安门、东安门、西安门和地安门，天安门为皇城正门；八门之说见于清代编纂的一些北京地方史志，将天安门之北的端门也算作皇城城门；四门之说亦常见于清朝，尤其是民间，仅包括天安门、东安门、西安门和地安门] , of which Tian'anmen, Di'anmen, Dong'anmen and Xi'anmen are the four referred to by the saying of "inner city 9 gates, outer city 7 gates, imperial city 4 gates(内九外七皇城四)".

#Damingmen: The main central southern gate of the Imperial city. Made from bricks, in imitation of the palace city gates. Its base is made from white marble in Xumi foundation style. The gate tower is in single-eaved Xieshanding style with glazed imperial yellow roof tiles. Five pillars on the front, three archways at the centre with white marble railings. Its name was changed to "Daqingmen (大清門 Great Qing Gate)" in 1644, the first year of the Shunzhi era when the Manchu first entered Beijing establishing the Qing dynasty. There is a white marble tablet on the gate upon which the name of the gate, "Daqingmen" is engraved in gold on an azure background. In 1912 when the Qing dynasty was overthrown and the Republic of China was established, the gate's name was changed to "Zhonghuamen (中華門 Gate of China)". The city planners decided to reuse the tablet and simply write the words "Zhonghuamen" on its back. However when the tablet was taken down and flipped over, they discovered the words "Damingmen (大明門 Great Ming Gate)" were written (in 1644 when the Qing dynasty was established and the Ming dynasty overthrown, they themselves thought of the idea and wrote the new name on the back of the original tablet). A tablet made of wood was then used. In 1954 with the recommendation of Soviet city planners working in Beijing, the gate was dismantled for the future Tiananmen Square. On its location now stands the Mausoleum of Mao Zedong
#Chang'anzuomen: Located southwest of Tian'anmen, it is similar to Damingmen. It is also called "Qinglongmen" or "Longmen" meaning "Dragon Gate" because during the Ming and Qing dynasties, the results to the imperial examinations were posted on the walls of this gate (successful passing of which would result in entering the forbidden city for imperial bureaucratic positions, normally forbidden to commoners). It was dismantled in 1952 when the Chang'an Avenue was expanded.
#Chang'anyoumen: Located southeast of Tian'anmen, it is similar to Damingmen. It is also called "Baihumen" or "Humen" meaning "Tiger Gate" because during the Ming and Qing dynasties, prisoners were executed just west of this gate. It was dismantled in 1952 when the Chang'an Avenue was expanded.
#Chengtianzhimen: It was renamed Tiananmen (Gate of Heavenly Peace) during the Qing dynasty. It is located at the Imperial city southern wall's midsection. The «Daming Huidian» refer to it as the main gate of the Imperial city, together with Duanmen forms the two gates that are part of an extension to the Forbidden city's main gate --- Wumen, while Damingmen is a secondary gate between the inner city's Zhengyangmen and imperial city's Tian'anmen. The platform is 13 metres high, it has a white marble bas of Xumi style, five archways. The gate tower is built in multi-eaved Xieshanding style, 9 rooms by 5 rooms (it was originally 5 rooms by 3 rooms during the early Ming dynasty), glazed imperial yellow roof tiles, 33,7 metres high. It was completely reconstructed in 1958, and subsequently repaired on several occasions.
#Duanmen: It is located directly north of Tian'anmen. It is similar to Tian'anmen. It can be seen as Wumen's outer gate, between the Imperial city's Tian'anmen and the Forbidden city's Wumen. This conforms to «Zhouli»'s five gate rule's "Zhimen" or "Kumen". [周礼记载，天子五门，自外向内依次为皋门、雉门、库门、应门、路门。北京皇城和宫城城门的设置参考了周礼，但五门对应位置有歧见。一种说法是大明门/大清门为皋门，承天门/天安门为雉门，端门为库门，午门为应门，太和门为路门；另一种说法是天安门为皋门，端门为雉门，午门为库门，太和门为应门，-{乾}-清门为路门。若按《周礼·考工记》中路门内为寝（即路寝）的说法，则端门应相当于雉门。若按同书中关于大朝、日朝和燕朝的区分来看，则端门相当于库门。若将端门看作是宫城的外门，则承天门也应算作宫城的外门。但《大清会典》将天安门定为皇城正门，午门为紫禁城正门，则端门应当为皇城正门的内门，或者宫城正门的外门。]
#Dong'anmen: Located slightly south of the imperial city's eastern wall's midsection. Single-eaved Xieshanding style with glazed imperial yellow roof tiles, 7 rooms by 3 rooms, three archways, each fitted with a pair of red-paint golden-nailed doors. It was destroyed in 1912 when Cao Kun's insurrection against Zhang Xun burned down the structure. In 2001 the remains of the site was cleaned and became the "Beijing Imperial City Site Park".
#Xi'anmen: Located slightly north of the imperial city's western wall's midsection. It was built similar to Dong'anmen. It was accidentally burnt down on the 1st of December 1950. a smaller scale model of the gate tower was built on its original site using the same materials of the original gate tower as commemoration.
#Beianmen: Located on the imperial city's northern wall's central vertical axis. It is the north gate of the imperial city. Commonly referred to as "Houzaimen" during the Ming dynasty [《光绪顺天府志》京师志三·宫禁下：“永乐十五年，始改建皇城于东，去旧宫里许……转西向北，曰北安门，即俗称厚载门是也”] . It was renamed "Di'anmen" during the Qing dynasty. It is similar to Dong'anmen, only slightly bigger in scale. It was dismantled between 1954 and 1956.

Palace City

Beijing's Palace city or "Forbidden city" because it was forbidden for entrance to the majority of the people, was completed in 1415 (the 14th year of the Yongle era). Its surrounding walls have a perimeter of 3,4 kilometres, a height of 10 metres, a base thickness of 8,62 metres, and a top thickness of 6,66 metres. There are also two rows of roof tiles glazed in the imperial yellow colour set on a triangular base of 0,84 metres in height. Both the interior and exterior sides of the walls are further reinforced with 2 metre thick bricks, the insides are made mostly of stones and rammed earth. It also has four corner guard towers built in combination-multi-eaved Xieshanding style. There are only four gates serving as passageways for the forbidden city, one on each side:
# Wumen is the southern facing gate, it is also the main gate, in alignment with the city's central axis, in direct alignment coming from the south northwards with outer city's Yongdingmen, inner city's Zhengyangmen, imperial city's Tian'anmen, and finally reaching the forbidden city's Wumen. It is built on a "凹" character shaped platform 13,5 metres high. Its gate tower is 9 rooms by 5 rooms multi-eaved veranda floored in design. With two side pavilion towers on each side, square in shape, 5 rooms by 5 rooms. The two "arms" stretching from the centre of the "凹" character shaped platform are commonly referred to as "hawk wings towers", there are towers of 13 rooms by 2 rooms on each of the "arms", at the end of the "arms" are square shaped pavilion towers respectively. At the left and right of the platform are sundials and many other time measurement apparati. There are three archways in the middle of the gate. They are regular rectangular shaped gates rather than arched ones of the outer city, inner city and imperial city gates. The two arms have one minor gate each near the intersection with the main "body" of the platform.
# Xuánwǔmén(玄武门) also called Shenwumen, not to be confused with Xuānwǔmén(宣武门) of the inner city gates, is the northern entrance to the forbidden city. Its gate tower is 5 rooms by 3 rooms multi-eaved veranda floored in design, without "hawk wing arms". It has three regular rectangular shaped gates. During the Ming and Qing dynasties, there was also another Beishangmen just outside of this gate, it was however dismantled in 1950.
# Donghuamen is the eastern entrance to the forbidden city, it has a similar design to that of Xuánwumen and Xihuamen.
# Xihuamen is the western entrance to the forbidden city, it has a similar design to Xuánwumen and Donghuamen.

Besides these, the «Qing Huidian» also records that there were six gates to the forbidden city, this is taking into account the two additional minor side gates of the Wumen's two "arms". [《光绪顺天府志》京师志三·宫禁下：“其紫禁城外，向南第一重曰承天门；二重曰端门；三重曰午门。魏阙西分为左掖门，曰右掖门。转而向东，曰东华门，向西曰西华门，向北曰元武门，此内围之八门也”。]

Moats, canals, and other watershed system

Yuan's Khanbaliq first established an extensive moat system in and around the city. In 1368, Ming troops entered Khanbaliq and rebuilt the northern walls slightly south of the original; they built the foundations of the new wall upon the piled earthen hill formed from digging the moat of Khanbaliq. They also built a new moat system for the three main southern gates of the forbidden/palace, imperial and inner city quarters. Then, these three moats were linked to the eastern and western moats of Khanbaliq. When the outer city was reconstructed during the Jiajing era, another moat surrounding the outer wall was built along.

The water of Beijing's moats are spring water diverted from Mount Yuquan and Baifuquan, northwest of the city. It follows Changhe and then splits into two tributaries at Xizhimen. One route goes east, forming the inner city's moat system, and then divides into two further routes at Deshengmen: one flowing south, the other east. The the other route enters Jishuitan in the south, the three lakes/seas of the former imperial gardens, and finally joining the moat system at Tongzihe. From then on, the water follows along the curvature of the city wall moat, and joins the city's southern moat system at Zhengyangmen. The eastern route turns 90 degrees south at the northeastern corner guard tower, and converges with the city's southern moat system at Dongbianmen's northwest; Another route goes westwards and then southwards, forming the outer city's moat system, it converges with the inner city's southern and eastern moat system at Dongbianmen, finally entering into Tonghui River [《光绪京师城内河道沟渠图》] .

The inner city's moat system is widest at Zhengyangmen's southeast, it is between 30 to 50 metres in width there; It is at its most narrow in the section between Dongzhimen and Chaoyangmen, a mere 10 metres in width. The moat is 3 metres at its deepest, and a mere 1 metre at its most shallow near Fuchengmen. The outer city's moat is more narrow and more shallow compared to the inner city's. From its many years of usage, at the end of the Qing dynasty, the artificial moat system had become no different from a natural river system.

There are water passageways located throughout Beijing's city walls, they help with the input and output of the city's water supply. There are seven passageways in the inner city: Deshengmen West (enters the inner city, 3 passages), Dongzhimen South (leaves the city, 1 passage), Chaoyangmen South (leaves the city, 1 passage), Chongwenmen East (leaves the city, 1 passage), Zhengyangmen East (leaves the city, 1 passage), Zhengyangmen West (leaves the city, 3 passages) and Xuanwumen West (leaves the city, 1 passage). There are three passageways in the outer city: Xibianmen East (enters the outer city, 3 passages), Dongbianmen West (enters the outer city, 3 passages) and Dongbianmen East (inner city and outer city's main drainage, 3 passages). The passageways have a foundation built of rammed earth with stone slabs and stone bricks, followed by a layer of bricks. Each passageway has two or three layers of iron railings, there are also soldiers on guard at these passageways [《明会典》卷二百，《光绪顺天府志》京师一] .

The moat system had a great influence on the daily activities of Beijing's commoners. From the Yongle era of the Ming dynasty until the mid-Qing dynasty, the southern moat system's eastern section were used as canals for the transportation of staple food for entrance into the city. During the winter months when the moat froze over, they were walked upon as shortcuts in and out of the city. When the commoners were leaving the city, they would often board boats by the city's eastern moat system, following the moat southwards, leave the city at Dongbianmen, enter onto Tonghui River which leads to the rural areas of Tongzhou. Every year during the Hungry Ghost Festival, people would place small ships with candlelight on the moats. During the winter months, there would be skating, and the ice would be sawed and saved in underground storages for use in the summer months. The moats are also home to many fishes and ducks.

In 1953, Beijing's moat system was measured at 41,19 kilometres, however as Beijing continued to expand, the moat system fell out of usage and became underground river systems. During the 1960s, the moat system of the three main southern gates became underground rivers. The western, eastern and northern moat systems became underground rivers in the 1970s. Today, only parts of the inner city's northern moat system, the outer city's southern moat system, the imperial city's moat system and the forbidden city's moat system are still seeing the light of day.

Besides the moat system, many lake system of the city were landfilled between the mid-1960s and the mid-1970s (e.g., Taiping Lake), totalling a land area of 33,4 hectares. Many others such as Longxugou and Lianhuachi decreased in size from partial landfills. However, the government also cleaned up many other lakes outside of the city, forming into larger lakes, subsequently built into public parks (e.g., Taoranting Park, Longtan Lake, Yuyuantan, and Zizhuyuan). Also some new river systems were built during the 1950s (e.g., Kunyu River and Jingmi Divertion River).

Yuan Khanbaliq

Yuan's Khanbaliq had 11 city gates, with the eastern, southern, and western sides having three gates per side, and the northern walls having two gates. The three eastern gates going from north to south are as follows: Guangximen, Chongrenmen and Qihuamen; The three southern gates going from west to east are as follows: Shunchengmen, Lizhengmen and Wenmingmen; The three western gates going from north to south are as follows: Suqingmen, Heyimen and Pingzemen; and the two northern gates going from west to east are as follows: Jiandemen and Anzhenmen.

During the early Ming dynasty, Xu Da was ordered to command the reconstruction of a new city, he found Yuan Khanbaliq's scale too great and thus for the ease of defending the city, built a new northern wall from rammed earth 5 kilometres south of the Yuan original. After the 4th year of the Hongwu era, the original Yuan's northern walls were abandoned, the northern gates of Jiandemen and Anzhenmen along with western wall's northern gate Suqingmen and eastern wall's northern gate Guangximen were abandoned as a result of the northern wall's abandoning. However, they were still used as secondary defense systems during the Ming dynasty. During the rebellion of An Da, there were still some Ming troops stationed at those gates.

Of the entire Yuan Khanbaliq's fortifications, only a small part of the northern and western sections of the city walls remain, as well as parts of the moat system in those areas. Suqingmen's barbican's wall of rammed earth's southern half can still be seen clearly.

Influences

Beijing is the capital city of the last three dynasties in the history of China, it is also the last imperial capital built in China's history. As the imperial political, cultural, military and commercial centre of the empire, the city planning and design of Beijing city represents some of the highest achievements in the field by the Ming and Qing dynasties, continuing and improving upon the city building and planning traditions of earlier dynasties [《中国古代城市地理》, p230] . The construction of Beijing's city fortification system took much of the ideas of Yuan's Khanbaliq and Ming's Nanjing, it is a conclusion to Yuan and post-Yuan pre-Republican era city planning styles. It is also the conclusion to China's 3200 year-long square-shaped dynastical city planning style, it is also a possible pinnacle in that regard closely matching the scale of Tang dynasty's Chang'an city planning. During the early Ming, when beijing was chosen as the new capital, Beijing was carefully planned, an axis running through the northern and southern walls' midpoints, dividing the city equally into two, quoting from the Confucian ideals of "居中不偏" and "不正不威". The entire city has the forbidden city's palace complex as its centre, with Longevity Mount (Jingshan) just north of the palaces. The Imperial city surrounds the palaces providing everything necessary for the Emperor's living style within the palace complex. The southern sections of the city are then allocated to officials and bureaucrats, while the inner and outer city are simply extra protection for the imperial city and the palace complex. The streets, avenues, and boulevards of the city are straight and wide, presenting an imperialistic ideal of order. Everything including buddhist temples, taoist temples, business districts, parks, imperial family residences are all planned in accordance with the imperial city's layout, its order being much stricter than that of the Yuan Khanbaliq, and also being on a bigger scale than Yuan's Khanbaliq [《中国古代建筑史》第四卷，p31] . On the design of the defences of the city, Beijing's fortifications also took in elements from Northern Song dynasty's «Wujing Zongyao» and Southern Song's already highly developed fortification construction expertise, using bricks and stones as foundations rather than rammed earth, this is the same with all of the structures of serving as the city's defences, including the watchtowers, the corner guard towers, the barbicans, the enemy sight towers, the sluice gate towers and so forth. Forming both planar and spatial defence for the city, it is dynastical China's best fortified city defence system, displaying the late dynastical China's greatest achievements in city fortification design [《中国古代城市地理》, p84] .

Beijing's fortifications were described by American Architect E.N.Bacon as "Man's greatest single architectural achievement on the face of the Earth" [ [http://gb.cri.cn/9523/2006/10/31/782@1280649_1.htm 《在北京生存的100個理由》尹麗川等著 遼寧教育出版社] ] . Sweden's scholar, Osvald Sirén, once published "The Walls and Gates of Peking" describing the fortification's majestic views, he wrote in his book, "if we compare it (Beijing city) to a giant's body, then the city gates are as the giant's mouth, used for the giant's respiration and speech, the entire city's life are centered around these city gates, like arteries. Those that enter and leave these city gates not only are carts, automobiles, pedestrians, and domesticated animals, but also people's thoughts, ideas, hopes and dreams, expectations and disappointments, and funeral processions and marriage ceremonies symbolising deaths and new lives. When you are standing by the gate's archway, you can feel the liveliness of the entire city, even the entire city's great expectations, all passing incessantly through these rather dark and narrow archways --- the city's heartbeat, pumping life force to this incredibly complex organism called Beijing, giving it life, giving it rhythm." [《北京的城墙和城门》，喜仁龙著] In the conclusion of the book, he presents a pessimistic view of the future of Beijing, whether these fortifications would be able to remain intact in their present forms. Indeed, the fortifications were subsequently dismantled one by one.

Preservation

As the call for a restoration of ancient architecture grows stronger and Beijing becoming the host city of the upcoming 29th Olympiad, there has been demands for a complete or partial reconstruction of the original "凸"-character-shaped city defence system. The recently completed reconstruction of Yongdingmen is one such example, and will most certainly be followed by others in the near future. A restoration of the city's Inner and Outer city moat system which will become part of the public waterway network, reconstruction of the three gates on the south of the city's central axis (and possibly all of the nine gates and three corner guard towers of the Inner city) are already on being discussed by officials. However, most of the original sites of the gates have become sites of major developments since their dismantlement, such as Fuchengmen, Chaoyangmen, and Xuanwumen, which are now busy roads with high rises. This presents much difficulty if the city government were to start reconstruction work there. There have also been some alternatives of reconstructing them at a nearby site where it is less crowded. Some of the more likely projects are the restoration of the remaining fortifications, and the reconstruction of parts of the city walls, which are less daunting and require much less funding. Between 2001 and 2003, the remaining section of the southern Inner city city wall's eastern sections located in the south of the Beijing train station were completely restored and opened to the public as the "Ming dynasty city wall site public park". Between 2005 and 2006, the remaining sections of Beijing eastern Inner city city wall's south section were restored and merged with the "Ming dynasty city wall site public park". Currently, the Southeastern corner guard tower is being restored, and when completed will join the southern wall east section and eastern wall south section as the "Ming dynasty city wall site public park". Restoration of Beijing Ancient Observatory's sections of the city wall and its enemy sight tower are under planning, as well as Zhengyangmen's barbican [参见《北京日报》、《北京晚报》在2003年至2006年对北京城垣复建计划的相关报道] .

ee also

*Chinese city wall
*Beijing Imperial City
*Beijing Imperial Palace
*Khanbaliq

References

ources

Reference literature

*《光绪顺天府志》，北京古籍出版社出版，ISBN 7530002430
*《钦定日下旧闻考》，（清）于敏中著，北京古籍出版社出版，ISBN 7530002422
*《天府广记》，（明）孙承泽著，北京古籍出版社出版，ISBN 7530002406
*《宸垣识略》，（清）吴长元著，北京古籍出版社出版，ISBN 7530002384
*《燕都丛考》，陈宗蕃著，北京古籍出版社出版，ISBN 7530000527
*《中国古代建筑史》第四卷，中国建筑工业出版社出版，ISBN 7112031249
*《中国古代建筑史》第五卷，中国建筑工业出版社出版，ISBN 7112031257
*《北京的城墙和城门》，（瑞典）喜仁龙著，北京燕山出版社出版
*《燕都说故》，北京燕山出版社出版 ISBN 7540207639
*《城记》，王军著，生活·读书·新知三联书店出版， ISBN 7108018160
*《明清北京城垣和城门》，张先得著，河北教育出版社出版
*《北京老城门》，傅公钺著，北京美术摄影出版社出版，ISBN 7805012377
*《水乡北京》，王同祯著，团结出版社出版，ISBN 7801307461
*《中国城市历史地理》，马正林著，山东教育出版社，ISBN 753282764X