Beneath its gently rolling hills lies Mammoth Cave, the world’s longest known cave system, offering a mystifying underground world of echoing chambers, cathedral-like tunnels, and prehistoric wonders.

MAMMOTH CAVE, Ky. — Though the federal shutdown has affected several national parks across America, Mammoth Cave National Park in Kentucky remains open, officials say. Visitors can still visit the ...

Mammoth Cave, the world's longest known cave system, stretches 426 miles under Kentucky. The cave's limestone began forming 330 million years ago when the region was submerged under an ocean. Visitors ...

The air is cool and damp. The light shining from behind is low and tinted, while a park ranger's hand hovers over a button. Then, a switch clicks. Light floods a chasm in the stone, a chamber called ...

The ongoing federal government shutdown shuttered Mammoth Cave National Park's guided cave tours in October, but there is still a way to make a trip out of the popular tourist destination in ...

About 340 million years ago, a tiny shark swam in the waters of the world’s longest cave system in Kentucky, its unusual mouth curved in a way that will ultimately end up defining its future legacy.