ellen 
Just an hour or so north of Chicago, near the Wisconsin border, Adeline Jay Geo-Karis Illinois Beach – State Park offers swimming/hiking/camping/picnicking! I went one hot afternoon in late August and found the beach a little rocky, but beautiful. There are also trails into the wetlands that offer up prime examples of the swampy marshes that used to cover the entire Lake Michigan area.
The sand is beautiful, the waves soothing, and the water pleasantly cool. I’d suggest to take along some shoes or toughen up your feet for wadding.
I found the nature trail very enjoyable. It brings you down around a river where turtles sunbathe.
So many surprising wildflowers and gold finches everywhere.
Worth an afternoon visit, you won’t be disappointed.