Northwest Side, Chicago
Community areas in Chicago refers to the work of the Social Science Research Committee at the University of Chicago, which divided the city of Chicago into 77 community areas which are officially recognized by the City of Chicago. These areas are well-defined and static. Census data are tied to the community areas, and they serve as the basis for a variety of urban planning initiatives on both the local and regional levels.
The Social Science Research Committee at University of Chicago defined seventy-five community areas during the late 1920s. At the time, these community areas corresponded roughly to neighborhoods or inter-related neighborhoods within the city. In the 1950s, with the city's annexations for O'Hare International Airport, a seventy-sixth community area was added. Other than the creation of the seventy-seventh community area in 1980 (by separating Edgewater from Uptown), boundaries have never been revised to reflect change but instead have been kept stable to allow comparisons of these areas over time.
Community areas are distinct from neighborhoods in Chicago. Community areas often encompass groups of neighborhoods. Although many community areas contain more than one neighborhood, they may also share the same name, or parts of the name, of some of their individual neighborhoods. Political wards of the Chicago City Council are also a distinct geographic concept but may be important in reading history or in modern contexts; they however are redistricted over-time and their boundaries change.
The city center area covers a little more than 4 square miles (10 km2), lying roughly between Division Street (1200 North) on the north, Lake Michigan on the east, 26th Street (2600 South) on the south and Halsted (800 West) on the west. This area is city's commercial hub. The three branches of the Chicago River meet in this area.
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