Geography of Chicago

The city of Chicago is located in northern Illinois at the south western tip of Lake Michigan. It sits on the St. Lawrence Seaway continental divide at the site of the Chicago Portage, an ancient trade route connecting the Mississippi River and the Great Lakes watersheds.

Geography

Chicago's present natural geography is a result of the large glaciers of the Ice Age, namely the Wisconsinan Glaciation that carved out the modern basin of Lake Michigan (which formed from the glacier's meltwater). The terminal moraines formed by the glacier today are low lines of hills in the southern suburbs. The flat plain that Chicago proper mostly lies on is the bed of glacial Lake Chicago, which was a larger precursor of Lake Michigan.

Topographical relief is so unusual in Chicago that what would be unnoticed hills and ridges in other locales have been given names. The highest natural point within the city limits is in the Beverly neighborhood at coord|41|42|12.5|N|87|40|37|W|. In pioneer days, this hill was called Blue Island, so named because at a distance it looked like an island in set a tractless prairie sea. In fact it, and the nearby Stony Island, were both islands in Lake Chicago. The diagonals Clark Street and Ridge Boulevard run along ridges that were once sandbars in the Lake.

One special feature of the Chicago area was the now-vanished Mud Lake in the Des Plaines River watershed. During heavy periods of rain or when the Des Plaines overflowed its banks due to downstream ice dams in the early spring, the river would flow through Mud Lake to the South Branch of the Chicago River, forming a favorite portage for early traders and creating the path of the future I&M and Chicago Sanitary and Ship Canals. When the city we know today was initially founded in the 1830s, the land was swampy and most of the early building began on low dunes around the Chicago River's mouth.

tatistics

According to the United States Census Bureau, Chicago has a total area of 606.1 km² (234.0 mi²). 588.3 km² (227.1 mi²) of it is land and 17.8 km² (6.9 mi²) of it is water. The total area is 2.94% water. The city has been built on relatively flat land, the average height of land is 579 feet (176 meters) above sea level. The centroid (geographical center) of the city is at at coord|41.840675|N|87.679365|W. [http://www.geomidpoint.com/index.html] Chicago, along with New York City and Los Angeles, California, are the three most populous cities of the U.S., yet Chicago is only half the other two cities' individual land areas.

The Chicago Metropolitan Statistical Area (MSA) consists of Cook county and five surrounding Illinois counties as well as the Chicago–Gary–Kenosha Consolidated Statistical Area (CSA) which is made up of nine counties, two of them in northwestern Indiana and one in southeastern Wisconsin.

Cityscape

Chicago has been at the forefront of skyscraper building since the late 19th century. Today Chicago can boast to having 5 of the 10 tallest buildings in the United States and 10 of the 50 tallest in the world.

By modern standards, Chicago has little reason to build up: being located in the Midwest, it has plenty of room to sprawl outwards on almost Euclideanesque flat ground. There is the Chicago River, which may bring some argument as to geographic restriction, but the impact of which was strongly lessened by the strict adherence to the Chicago grid across the river.

Today, Chicago is going through a massive skyscraper building boom, with projects like 55 East Erie (the tallest residential building in the U.S. outside New York City) and Trump International Hotel (to be completed in 2007, it will be the fourth tallest in Chicago and the tallest building built in the U.S. for nearly three decades) breaking ground frequently. All this can really be attributed to precedent: Chicago has always had a history of frantic skyscraper building, mostly beginning after the Great Chicago Fire, and since this time developers simply follow the pattern set before them.

ee also

*Chicago River
*Chicago Sanitary and Ship Canal
*I&M Canal
*Lake Michigan