While in the Chicago area last week - I had some time to go to Illinois Beach State Park. Located just south of the Wisconsin State Line, Illinois Beach State Park sits along Lake Michigan. The park is located about an hour north of Chicago, but amazingly you can see the Chicago skyline from the park!
There are a lot of various recreational and lodging opportunities at Illinois Beach State Park. Swimming and boating in Lake Michigan are obvious activities, but there also over seven miles of hiking trails along with bike trails and nature preserves. The park is split into two different sections, North and South, as it is divided by the Zion Nuclear Power Plant. Camping is a popular activity but there is also a 92 room resort and conference center on site.