Prompted by the discovery of Green Oaks, Illinois earlier this week, I went searching for a list of all of the Chicago suburbs. Instead, I found a discussion about where exactly the Chicago suburbs end. Here is an expert talking about this very issue in summer 2018:
The best definition of where the “suburbs” are, according to Ellis, is probably the boundaries of the Chicago-Naperville-Joliet Metropolitan Statistical Area…
But calling everything inside those boundaries “the suburbs” is probably too simple…
So, Ellis said, the suburbs end to the west at the Fox River, to the south along the Lincoln Highway, and stretch along the train lines as far south as Michigan City, IN and as far north as Kenosha, WI.
The second map probably also conforms to cultural understandings in the region about what is really a suburb. There are places that could be within the far-flung orbit of Chicago but do not think of themselves or are not regarded by others as true suburbs.
This is an issue for many metropolitan regions, particular due to two changes:
1. Suburban areas keep developing further from the central city.
2. More people commute suburb to suburb rather than into the central city on a regular basis.
With more housing available further from the city as well as the presence of jobs in far-flung job centers, more residents can be part of a metropolitan region even if they rarely make a trip into the big city or do direct business with the big city.