Best Midwest State Parks
Iowa: Maquoketa Caves State Park
Cornfields and combines feel eons away from the lush and strangely exotic landscape at Maquoketa Caves State Park (30 miles south of Dubuque), where a long wood staircase descends from a concrete picnic area into an almost prehistoric world. Towering stone walls, moss-covered rocks and an emerald canopy unfold around the Maquoketa Caves' 16 caves and crawl spaces. Ducking under low-hanging rocks and clambering along a roller coaster of steps, visitors feel like real explorers. Bring a flashlight -- and a towel to wipe mud off your shoes. (563) 652-5833
Update: Check the park website before you go for cave accessibility; in May 2010, Iowa's Department of Natural Resources closed state-owned caves that bats use for hibernation to help slow the spread of a disease that is killing bats across the eastern United States.