I thought I'd give you a little Chicago history too.
Chicago is where it is because of geography. When us Europeans were first colonizing the area, most transport was by water. Chicago was a perfect spot, because, when it was wet, and not frozen, there was kind of a swamp where Chicago is now.
(Chicago is said to mean "bad smell", or "wild onion")
This was a very important swamp, because on one end, the water flowed into Lake Michigan. On the other end, the water flowed into the Chicago River, which eventually made its way into the Mississippi River.
So Chicago was the connecting point between the two great waterways of North America.
Later, during the railroad age, all the railroads had to go south around Lake Michigan, and then curve back north around Chicago.
In fact, because of geographical problems, the first railroad to connect eastern and western Canada also went through Chicago - the Soo line.
So there are still lots of train switching yards in the Chicago area as well. And some train museums, although the big one is pretty far out of town. There is still even a big train station there.
And Chicago grew up with trains, so there are lots of linear suburbs, and lots of people still ride the train to work.
When I lived there, the Chicago Transit Authority was dropping off a million people in downtown on State Street alone. There was a subway under the street, an elevated line above, and it was a bus only street. Cars are now allowed on the streed, but the subway and the El are still going.
