The Art Institute of Chicago is truly one of the world's greatest museums, on par with Le Louvre and the Guggenheim. It contains 2 of the most famous, if not most recognized, American paintings: Nighthawks by Edward Hopper and American Gothic by Grant Wood.
Tuesdays are ""free days"" with no admission fee. Whichever day you go, I'd say get there early. You'll need to make a few visits to see everything.
Pros: great collection, great exhibits, beautiful building
Cons: crowded on weekends
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