From prehistoric sharks to unusual flowers: What’s inside the world’s largest cave

Mammoth Cave National Park, home to the world’s longest known cave system, stretches for more than 680 kilometres, and counting, into the Earth. What began as a limestone labyrinth has turned out to ...
Morning Overview on MSN

World’s longest underwater cave system runs 524 km, dwarfing Grand Canyon

The world’s longest underwater cave system now stretches an astonishing 524 Kilometers, a hidden labyrinth that, in raw length, outstrips the Grand Canyon. Threaded beneath Mexico’s Yucatán Peninsula, ...
Travel + Leisure

This National Park Is Home to the Longest Cave in the World—and Only 426 Miles Have Been Explored So Far

Mammoth Cave National Park in Kentucky is home to the world’s longest cave system, with over 426 miles of mapped underground passages. While here, visitors can hike the Cedar Sink Trail and explore an ...