Explore Mammoth Cave National Park, the longest cave system on Earth, featuring the richest known habitat for cave wildlife in the world. It may be difficult to think of caves as spacious and grand, ...

longest, and wildest caves. At dusk, a swarm of bats disperses to hunt in the rainforest surrounding Deer Cave. One of the planet’s largest underground passages, it holds more than two million bats.

MANILA, Philippines — The Department of Public Works and Highways (DPWH) expects to finish the excavation works of what would become the longest tunnel in the Philippines by the second quarter ...