As home to the longest cave known in the world today, you have to see Kentucky‘s Mammoth Cave to believe it. With 356 miles of known cave trails, the explorers are still finding new links everyday. See the amazing stalactites, stalagmites and formations that were created millions of years before you were born. The park offers tons of guided tours to cover what you need – easy, hard, long, short. Just check the website to see what works for you. Not so interested in going underground? Surprisingly, Mammoth Cave offers 70 miles of wooded trails and 52,000 acres of secluded natural preservation, as well as spelunking adventures.

See and save more places to create your own itinerary or modify a Bindu itinerary.

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  Photo by John Beagle
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  Photo by dozier.donald