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Mammoth Cave National Park Discovers Miles and Miles of New Underground Passages

As if 412 miles of cave wasn't enough...

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Kentucky’s Mammoth Cave, the world’s longest cave at 420 miles, has proven itself to be a bit of an overachiever. This month, the Cave Research Foundation, a local nonprofit responsible for mapping out pretty much all of Mammoth’s subterranean passageways, announced that researchers had discovered 8 additional miles of cave system.

For the past 60 years, the CRF, which is entirely comprised of volunteer cavers, has rappelled, crawled, and dove into the cave system, documenting their finds (which include some 130 species of wildlife, like the Eyeless Cave Fish) for future explorers. Says Dr. Rick Toomey, the park’s Cave Resource Management Specialist: “Without CRF exploration and mapping, Mammoth Cave would potentially still be a 44-mile-long cave system.”

The record-breaking cave system, which, over the past fifty years, has been found to connect to others, like the Flint Ridge system, Proctor Cave, and Roppel Cave, is expected to continue growing: the park estimates there is potential for some 600 additional miles of twisty-turny cavern hidden below Kentucky.

While the new passages aren’t currently open to visitors, you can see the world’s longest cave for yourself on one of the 11 tours the park is currently offering. Routes range from a quarter-mile to 4 miles in length.