Brownie323leader

We are in need of a clean, safe gym or room with access to a bathroom facility for a trip this summer with the girl scouts. Must accomodate approx. 15 to 20 people (sleeping bags). I have heard there is a military base that lets you use their gym near chicago. Maybe Northwestern also?? Prefer downtown area. Only needed for sleeping-two nights in July or August 2003. Need to keep costs down. Are there any???