Six miles (10km) of trails thread through the state park, wriggling out towards cave openings and past twisted rocky bluffs. The park’s crown jewel is the Dancehall Cave, a riot of flowstone and dripstone formations that crawls out for some 1,100 feet (335m). There are about 12 more caves beyond the star sight – some with needle-tight passageways for pro spelunkers. Once you’re adventured out, the shady campsite provides the perfect respite.

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Midwest Marvels: This Is Your State’s Best Campsite