New Discovery Adds 8 Miles to the World's Longest Cave System

Additional passages were recently found at the Mammoth Cave National Park in Kentucky.

With more than 400 miles of known passages, Mammoth Cave is the longest cave system in the world. Located in Kentucky, the system of passages is even bigger than previously believed.

Mammoth National Park announced this week that The Cave Research Foundation uncovered eight additional miles of passageways, making the system at least 420 miles long. The passages were mapped and thoroughly traversed by members of the nonprofit organization. The park said "there is no end in sight," however, suggesting there may be even more to discover down the line.

"THE LONGEST CAVE IN THE WORLD IS NOW EVEN LONGER!!!" Mammoth Cave National Park announced in a Facebook post over the weekend.

Rick Toomey, the park's cave resource management specialist, credited the Cave Research Foundation with Mammoth Cave's recognition as the world's longest cave, according to the Associated Press (via U.S. News & World Report). The park and the organization have had a longstanding partnership.

"The Cave Research Foundation is fundamentally the reason that Mammoth Cave is recognized as the world's longest cave," he told the outlet.

Mammoth Cave National Park offers guests the opportunity to take tours of the cave for a fee. Visitors are also welcome to explore outside of the cave via the Beneath Your Feet program, which includes several curated trails. Fees range from $6 and up and depend largely on age, difficulty, and whether or not you're going on a guided or self-led tour.

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Caitlyn Hitt is Daria IRL. Don't take our word for it—find her on Twitter @nyltiaccc.