ILLINOIS.......has some surprises, one of which is how much down near the Missisippi is boggy, before you get up into the familiar farmland disticts. One thing I didn't reckon on, either, was that, if you're going to Chicago, you really should start planning which side of Chicago you want when you enter the state. The central highways will put you into Chicago proper, the western, like I-55, will deliver you to the western suburbs, and the northern will get you to the northern suburbs. Not to mention the fact that everything has to route around the lake, and through Gary, Indiana.
One thing that did impress me greatly is the way Chicago moves traffic along. The signs advise trucks to keep right, and they do. This tears up the righthand pavement a bit, and there are epic potholes, but this means that cars don't have to weave in and out among trucks. If a car goes too slowly (below 80) it gets honked at. If it dithers at a light, it gets honked at. Traffic moves, and if you miss your exit, you replan and recalculate. It's remarkable how many cars can pass a green traffic light, and how fast traffic gets you from one small suburb to the other. In a week I began to get the lay of the land, never visited Chicago downtown, but I'm getting pretty good on the suburbs.