Well, the there are a few options that come to mind, however, you should stick to something out in the 'burbs as a base and drive into the city if you plan to sight-see. Illinois Beach State park is nice, right on the lake and borders the Ill/WI border. Further to a west suburb, there is a KOA in Union, IL. Nice place, Railway museum really close and a cool place to visit. I am sure some of the chicago people will chime in soon. Do you also plan to stay somewhere in central Illinois or down by st. lewey??
2015 Rushmore Springfield
Disc Brake upgrade, Goodyear G614 tire upgrade
RV FLEX-ARMOR roof, Mor-Ryde IS suspension
2017 F350 Dually 4x4 6.7 Bronze Fire