TSIL436 = The Secret in Locker 436
Meet the vast Mammoth Cave in central Kentucky.
This National Park is the longest cave system known in the world. Since the 1972 unification of Mammoth Cave with the even-longer system under Flint Ridge to the north, the official name of the system has become Mammoth–Flint Ridge Cave System.
The area was established as a national park on July 1, 1941, a World Heritage Site on October 27, 1981, and an international Biosphere Reserve on September 26, 1990.
The park’s 52,830 acres include The Green River, with a tributary called the Nolin River feeding into The Green River just inside the park.
Mammoth Cave is the world’s longest known cave system with more than 400 miles of surveyed passageways, which is nearly twice as long as the second-longest cave system, Mexico’s Sac Actun underwater cave (which we cover in our next blog post).