Chicago, whether your interest is jazz or the blues, football (the sort that takes three hours for sixty minutes of play), baseball, small independent craft breweries, the shopping, the restaurants & bars or hanging out by the lake shore – apparently there are even museums and art galleries; the evocative and defining thing about Chicago is The L.
The mostly elevated rapid transit system serving the centre and the suburbs – taking you pretty much anywhere for five dollars a day (and, if you work it out quickly enough, bringing you downtown from the airport).