Quadripoint

In geography, a quadripoint is a point on the Earth that touches four distinct regions. Such points are often called "four corners", from the corners of the four regions meeting there. [One could argue that, if one region lies on one side of a straight line border, and the other three are on the opposite side of this line, there are only three "corners" plus a straight line. However in geometry the straight line in this context would be considered to form a straight angle measuring 180°.]

International quadripoints

At present there are no generally recognized quadripoints involving four different countries, although a claim is often made that one exists at coord|17|47|32|S|25|15|52|E between Namibia, Zambia, Zimbabwe and Botswana at the thalweg confluence of the Zambezi River with the Chobe River near Kazungula. The various boundary definitions involved are subject to differing and disputed interpretations; only one combination of interpretations and river conditions might have produced a quadripoint, but that combination never obtains in reality. [cite book| title = African Boundaries: A Legal and Diplomatic Encyclopaedia | first = Ian | last = Brownlie | coauthors = Ian R. Burns | pages = 1098-1108 | chapter = Botswana-Zambia (Quadripoint issue) | publisher = C. Hurst & Co. | location = London | year = 1979 | id = ISBN 0-903983-87-7; summarized at [http://home.worldonline.dk/jesniel/border/african_tripoints.htm#bwnazm African tripoints: Botswana-Namibia-Zambia] by Michael Donner / Jesper Nielsen.] [cite book| title = International Law and the Protection of Namibia's Territorial Integrity | first = S. | last = Akweenda | pages = 201-3 | chapter = VI: Quadripoint Theory | publisher = Martinus Nijhoff | location = Netherlands | date = 1997-04-23 | id = ISBN 90-411-0412-7]

Close calls

If the Kazungula case above is not accepted as a quadripoint, it is the place where tricountry points are closest together, as the distance between the tripoints is believed by the most careful authorities to be on the order of 100 meters.

Where two tripoints occur very close to each other, they can look like a quadripoint on a map of insufficient resolution. For example, the Kazakhstan/Russia/People's Republic of China tripoint at coord|49|5|59|N|87|18|45|E is only 39 km from Tavan Bogd Uul, a Russia/Mongolia/People's Republic of China tripoint. It may look like a quadripoint on some maps, but at more detailed resolution, it is clear that Kazakhstan and Mongolia never touch. [coord|49.04|N|87.4|E|]

An even closer example of this is between the tripoints of Armenia/Turkey/Nakhichevan, Azerbaijan and Iran/Turkey/Nakhichevan, Azerbaijan, which are about 9 km from each other at coord|39|41|0|N|44|48|30|E.

Although four countries border Lake Chad, there is no quadripoint of Chad, Niger, Nigeria, and Cameroon within the lake. The two tripoints are about 86 km apart.

Similarly, the Gulf of Aqaba in the Red Sea borders four countries, but does not contain a quadripoint of Jordan, Saudi Arabia, Egypt, and Israel.

Some political maps of the South Pacific enclose many island nations within straight lines drawn along parallels of latitude or meridians of longitude, often with a maritime quadripoint indicated for Solomon Islands, Tuvalu, Kiribati, and Nauru. [One such map is at |accessdate=2006-12-10]

Previously existing would-be four-country points

Between 1830 and 1920 there was a quadripoint at the convergence of Belgium, Prussia/Germany, the Netherlands, and Moresnet. coord|50.75|N|6.02|E| [http://commons.wikimedia.org/wiki/

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] [http://nl.wikipedia.org/wiki/Afbeelding:Vierlandenpunt.jpg] This point has often been called a quadricountry point, though Moresnet was never truly a country but rather only a neutral territory or condominium of the Netherlands and Prussia (originally), and of Belgium and Germany (ultimately).

From 1922 to 1991 there was a de facto quadripoint coord|29.1|N|46.55|E| between Iraq, Kuwait, Kingdom of Nejd/Saudi Arabia and the Saudi-Iraqi neutral zone, although precise boundaries were never specified by the three sovereign states.

Fewer than four countries

There are quadripoints where four border lines touch each other at one point, but involving fewer than four countries. This occurs with a practical exclave which touches the main territory (or another exclave) at a single point. The Belgian enclaves H1 and H2 in Baarle-Hertog touch each other at one such point, while the Netherlands also crosses it. [See The Baarle Enclaves website, including [http://www.grenspalen.nl/archief/baarle-nassau-in-english.html : overview with photograph of the H1-H2 quadripoint] and [http://www.grenspalen.nl/archief/baarle-map%20met%20enclave-aanduidingen-center.jpgMap including H1 and H2 enclaves] ]

Similarly, the Austrian town of Jungholz lies totally within Germany except that it borders Austria at one single point.

Cooch Behar in India is linked with Bangladesh by at least one such point (and very possibly a second).

econdary quadripoints

A secondary quadripoint (or "quadrisecondary point") is the meeting of four political subdivisions (for example, provinces, states, or cantons). The four subdivisions may all belong to one country, or they may involve two or three different countries.

By analogy, one could speak of tertiary quadripoints ("quadritertiary points") where, for example, four different counties meet at one point, and quaternary quadripoints ("quadriquaternary points") where four municipalities meet, etc. However, these lesser categories would not have been considered as interesting as primary or "world class" quadripoints, if indeed any such quadricountry points had ever actually existed. For example, many of the counties of Nebraska or the towns of Maine are demarcated as squares in a grid.

Trinational

At coord|54.36435|N|22.79228|E|, there is a trinational secondary quadripoint: to the northwest is Russia (specifically the Russian exclave Kaliningrad Oblast); to the northeast Lithuania; and to the southwest and southeast two Voivodships (provinces) of Poland: Warmian-Masurian Voivodship and Podlaskie Voivodeship. [http://maps.msn.se/map.aspx?C=54.36435,22.79228&L=EUR&S=800,740&A=49] The quadripoint exists thanks to the way the border between Poland and Russian SFSR was defined in 1945 by the Potsdam Agreement.

At or around coord|19|N|52|E|, there appears to be another trinational secondary quadripoint: to the north is Saudi Arabia, to the southeast is Oman, and to the southwest two Governorates of Yemen: Hadhramaut Governorate to the westsouthwest and Al Mahrah Governorate to the southsouthwest.

Binational

The three German states Bavaria, Saxony, and Thuringia (the two tripoints are about 20 km apart), do not form a quadripoint with the Czech Republic; nevertheless it is frequently commented on.

A similar seeming quadripoint exists near Biaufond at coord|47.1655|N|6.86|E| between the Swiss cantons of Jura, Neuchâtel, and Berne on the one hand, and the French département Doubs on the other hand. In this case, the two tripoints are separated by only about 250 m/830 ft.

On the border of Sweden and Norway, at coord|65.11888|N|14.32592|E|, there appears to be a binational secondary quadripoint where two Counties of Norway, Nord-Trøndelag and Nordland, meet two Counties of Sweden, Västerbotten County and Jämtland County.cite web | url=http://groups.yahoo.com/group/BoundaryPoint/message/19589?l=1 | accessdate=2006-06-20 | work=BoundaryPoint (Yahoo! Groups) | title=an apparent nose2janontvb binational quadripoint | author=Kallos, Aletheia | date=2006-06-08 |] [http://maps.msn.se/map.aspx?C=65.11888,14.32592&L=EUR&S=800,740&A=49]

Another binational secondary quadripoint appears to exist on the border of Argentina and Uruguay where the Argentinian provinces of Corrientes and Entre Rios also very probably meet the Uruguayan departments of Artigas and Salto.

National

The Argentine provinces of La Pampa, Río Negro, Mendoza and Neuquén form a quadripoint at coord|37|34|00|S|68|14|00|W|region:AR_scale:2000000, though Rio Negro has disputed this since a 1966 resurvey cast the exact boundary convergence into some doubt.

The Four Corners is the only point in the United States of America where four states meet: Colorado, Utah, New Mexico, and Arizona meet at right angles.

There has been an analogous Four Corners in Canada at coord|60|N|102|W|region:CA-SK_type:city since the creation of Nunavut in 1999; it meets Saskatchewan at a point, with Manitoba and the Northwest Territories at the other corners. Before 1999 this was a tertiary quadripoint, with Manitoba, Saskatchewan, and the then existing Northwest Territories districts of Mackenzie and Keewatin.

Four provinces of the Philippines meet at a point on Mindanao island, probably at one of the three peaks of Mount Apo: Bukidnon, Davao del Norte, Davao del Sur, and Cotabato.

There are two quadripoints in Switzerland where three cantons meet. At each, a practical exclave of one canton touches its parent, while two other cantons touch each other. One is near coord|47|24|51|N|7|22|33|E|region:CH_scale:20000, where the municipality of Roggenburg is cut off from its parent Basel-Country by Jura to the south and an exclave of Solothurn to the north. The other is near coord|47|19|20.5|N|7|33|30|E|region:CH_scale:20000 where Jura again touches Solothurn, cutting off the municipality of Schelten from its parent canton of Bern. [cite book |last=Schuler |first=Martin |coauthors=Pierre Dessemontet, Dominique Joye |others=with the collaboration of Manfred Perlik |title=RECENSEMENT FÉDÉRAL DE LA POPULATION 2000: LES NIVEAUX GÉOGRAPHIQUES DE LA SUISSE |url=http://www.bfs.admin.ch/bfs/portal/fr/index/themen/raum_und_umwelt/uebersicht/blank/publikationen.Document.64477.html |format=PDF |accessdate=2007-01-04 |year=2005 |month=July |publisher=Swiss Federal Statistical Office |location=Neuchâtel |language=French |pages=p. 22, fn. 12 |quote=Juridiquement ..., un seul point de contact définit la qualité de territoire limitrophe. ... ce point de droit a permis que la commune de Roggenburg puisse changer de canton (d'abord vers Berne, puis vers Bâle-Campagne). De même la commune de Schelten n'est pas considérée comme une exclave du canton.]

Other countries that enjoy very probable (or positively confirmed) secondary quadripoints are Andorra, Bulgaria, the Dominican Republic, Gabon, India, Jamaica, Liechtenstein, Mauritania, Oman, Sudan, Uganda, and Vietnam.

United Kingdom

An analysis of county quadripoints in the United Kingdom is complicated by the fact that the borders and numbers of administrative counties have changed several times in the last century (see Administrative counties of England). No true quadripoints remain in the United Kingdom.

Until the late nineteenth century, one quadripoint did exist; near Evenlode in Gloucestershire, is "Four Shire Stone", [Ordnance Survey grid reference for Four Shire Stone: oscoor|SP231321_region:GB_scale:25000|SP231321] formerly at an intersection of Gloucestershire, Oxfordshire, Warwickshire, and a detached fragment of Worcestershire. However, the fragment has been reassigned, leaving only a tripoint around ten miles (16 km) from modern Worcestershire. [cite book |title=The Batsford Guide to the Industrial Archaeology of Central Southern England: Avon County, Gloucestershire, Somerset, Wiltshire |isbn=0713413646 |first=C. A. |last=Buchanan |coauthors=Robert Angus Buchanan |publisher=Batsford |year=1980 |pages=p.91]

In addition there are a few near misses. The most famous lies south west of Stamford – where Rutland, Lincolnshire, Cambridgeshire and Northamptonshire seem to meet at a point. (coord|52|38|25|N|0|29|40|W|) However, the location actually consists of two tripoints around 20 metres apart. [cite web|url=http://www.blanchflower.org/tripoints/quad.html|title=A real quadripoint?|publisher=blanchflower.org]

In addition near East Grinstead, the East Sussex-West Sussex-Surrey and East Sussex-Surrey-Kent tripoints are only a mile apart. Similarly the Staffordshire-Warwickshire-Leicestershire and Warwickshire-Leicestershire-Derbyshire tripoints are again around a mile apart. And until 1965, the two tripoints formed by Gloucestershire, Oxfordshire, Wiltshire and Berkshire near Lechlade came very close to one another. (coord|51|41|20|N|1|40|37|W|).

Five or more regions

At subnational level, one can find even more than four divisions converging at a point.
* Those five Parishes of Saint Kitts and Nevis that are located on the island of Nevis meet on Nevis Peak: Saint George Gingerland Parish, Saint James Windward Parish, Saint John Figtree Parish, Saint Paul Charlestown Parish and Saint Thomas Lowland Parish

quintipoint:
* Five counties in Florida meet within Lake Okeechobee: [ [http://www2.census.gov/geo/maps/general_ref/stco_outline/cen2k_pgsz/stco_FL.pdf Counties of Florida map] from U.S. Census Bureau.] Okeechobee, Martin, Palm Beach, Hendry, and Glades.

* In the Philippines:
**Municipalities of Tagkawayan, Quezon Province; Labo, San Vicente and San Lorezo Ruiz, Camarines Norte; and Del Gallego, Camarines Sur
** Cities of Cadiz, Sagay, Silay and Talisay, and municipality of Calatrava, Negros OccidentalFact|date=July 2008
** Municipalities of Carmen, Batuan, Bilar, Dimiao, and Valencia, Bohol
** Municipalities of San Miguel, Ubay, Alicia, Dagohoy and Pilar, Bohol
** Malaybalay City, Sumilao, Baungon, Talakag and Lantapan, Bukidnon
** Municipalities of Carmen, Aleosan, Pikit and Kabacan, Cotabato; and Pagagawan, Maguindanao
** Municipalities of Tibiao and Barbaza, Antique; Madalag and Libacao (a close call?), Aklan; and Jamindan, Capiz

Tertiary sexipoint:

* Municipalities of Basey and Marabut, Samar; and Balangkayan, Llorente, Balangiga and Lawaan, Eastern Samar, Philippines

Cases of Tertiary octopoints:

* Eight municipalities or towns in Albay, Philippines including Legazpi City meet on the crater of Mayon Volcano.

* Eight municipalities (Aura, Masku, Mynämäki, Nousiainen, Pöytyä, city of Turku, Vahto & Yläne) meet on Kuhankuono boundary mark [ [http://kansalaisen.karttapaikka.fi/linkki?text=Kuhankuono+octopoint&scale=16000&y=6737206&x=1577374&lang=en-GB Kuhankuono octopoint from National Land Survey of Finland map] ] in the Kurjenrahka national park in Finland Proper. In 2009, Pöytyä and Yläne will merge, "demoting" the point into a seven-point.

References

This article was originally translated from the Dutch-language wiki article , as of 2006-06-20 [http://nl.wikipedia.org/w/index.php?title=Vierlandenpunt&oldid=4288775] , with the assistance of [http://www.systranbox.com SystranBox online machine translation] .

ee also

*Tripoint
*Tri-state
*Tri-state area
*Land borders
*Four Corners (Canada)
*Four Corners (United States)
*Four Corners Monument
*Moresnet
*List of sets of four countries that border one another
*Borderless country

External links

* [http://members.aol.com/marismits/LoclGeo.htm Geographical Curiosities: Local Geography] a larger list of quadrisecondary points, without references.