Carlsbad Caverns – USA (16/20)

In the heart of New Mexico, Carlsbad Caverns National Park boasts 119 caves, with the main cavern measuring 8.2 kilometers (5.1 miles). Known for its breathtaking stalactites, stalagmites, and vast chambers, the cave’s beauty is only rivaled by its diverse ecosystems, including colonies of bats that make their nightly exodus during the warmer months.