Mammoth Cave

Mammoth Cave National Park in west-central Kentucky is the longest cave system known in the world with more than 420 miles of surveyed passageways. The park is 52,830 acres and two rivers - the Green River and a tributary called the Nolin River - flow through it. The caves are located just below the water table, which means that they are constantly being replenished with water. This also means the caves are subject to flooding, and many have been closed to the public for safety reasons. The national park is open year-round and offers a variety of activities for visitors to enjoy.