The city boundaries of Chicago contain many tens of communities, some with a polished urban character, others with industrial grit or suburban charm. Only in recent decades has the conglomeration gained a cohesion somewhat akin to other concentrated metropolises, although a description of the city as a "sprawling plexus of industrial towns, local shopping districts, crowded tenement neighborhoods, [and] green and spacious settlements" from a 1939 guidebook seems well-recognizable some sixty-five years later.

The heart of "Tourist Chicago" lies naturally in its downtown area, focused in the Loop but spilling quite a ways over into the Near North and Near South sides of the city and with scattered sites in Hyde Park, Lincoln Park, and the Far North as well. Chicago west of the lake becomes largely a local's world of ethnic neighborhoods, industrial corridors, gleaming churches, lovely parklands and suburban-like residential enclaves.

WildOnions.org has divided the city of Chicago into twenty-one distinct regions by grouping together sections of the city's official Community Areas, listed alphabetically above. Thematic map and regional boundaries developed by WildOnions.org. Chicago geographic data and source map from Northeastern Illinois Planning Commission.