If you don't mind boondocking, then you can park in the central city just a block from Lake Michigan. There is a large truck staging parking lot just south of McCormick place at Lake Shore drive and I55 that offers gated parking for large vehicles. There is of course a parking fee but it is minimal. The lot is big enough so that, under most circumstances, you will not be bothered by the semis.
This lot is very convenient to all of Chicago's main attractions - many are within biking distance.
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