32 Underrated National Parks Perfect for Avoiding Summer Crowds
19. Mammoth Cave National Park, Kentucky: World's Longest Cave & Woodland Calm

Mammoth Cave National Park protects the world's longest known cave system, offering fascinating ranger-guided tours through its vast subterranean chambers. Above ground, the park boasts extensive hiking trails through lush Green River Valley woodlands, perfect for peaceful strolls, kayaking, or fishing. While the cave tours can be popular, the expansive surface trails offer abundant opportunities for solitude and quiet immersion in a beautiful Kentucky forest landscape, a unique blend of underground wonder and surface serenity.