If you've ever been intrigued by the subterrainian world, plan a stay at the Horse Cave KOA. It lies in the heart of one of the most significant cave regions on the planet. Beneath the area's rumpled hills, eons of dripping and flowing waters have worn through the limestone bedrock, creating a maze of underground rooms, rivers and sinkholes. Nearby Mammoth Cave National Park preserves the world's largest known cave system. Sign on for a tour for an unforgettable introduction to this geological wonder. If you're up for adventure, try the belly-crawling six-hour Wild Cave Tour.

Cleanup is easy at KOA, where you'll find hot showers, laundry facilities and new owners. Kamping Kabins, shady pull-thrus, a swimming pool, mini golf and a playground for the kids make this a relaxing base. In the fall, the trees will reward you with glorious color.