A group of us did a downtown Chicago river cruise last summer which was really cool, and the Navy Pier fireworks on Wednesday and Saturdays are always fun to watch on the water! As far as Marina's, Dusable seems to be right in the heart of the action and is directly connected to the river walk and the Lake shore bike/run path. As far as reservations the only thing I can tell you is it might not be as easy to get reservations as it is in Michigan...you guys have an awesome municiple system! Maybe someone else can chime in here with more experience with the Chicago marina system...we always cruise home after spending the day in Chicago considering our marina is only 25 miles away.
Just curious....Will you be crossing the lake and going down the Wisconsin/Illinois side or hugging the shore and heading south towards Indiana, and also kind of boat are you making this trip in? Good luck with your planning.

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