Cave-in-Rock State Park in southern Illinois is famous for a 55-foot-wide cave that opens onto the Ohio River. The cave was once used by river pirates and outlaws who preyed on travelers, and its rugged, dramatic setting lends it a colorful history. Visitors can walk into the cave and explore the bluff overlook, which provides sweeping views of the river and the Kentucky shore. Trails, picnic areas and a campground make it a good stop for travelers and families, and the ferry crossing nearby adds to the scenery. There is no vehicle entry fee, and camping fees vary by site, from $8 to $45 per night. It is well worth a stop in the Shawnee Hills region.