For tens of thousands of years, caves have captured and fostered the human imagination. They're the closest thing to an alien world most of us will ever experience, and much like the bottom of the ocean, they continue to demonstrate how little we know about our own planet. Here's a look at some of the world's most stunning, inspiring, and spectacular caves.
Deer Cave (Malaysia)
Deer Cave in Malaysian Borneo was formed when freshwater eroded the limestone that also forms Gunung Mulu National Park's famous karsts, jagged blades of rock jutting above the trees. The cave picked up its name from the animals that congregated near its opening to lick salt from the walls, but it is more commonly associated with bats, who stream out of the entrance daily. Visitors can reach the pit via a walkway that cuts through the canopy of the jungle, itself home to several types of monkeys and and more than 250 species of birds.
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