Lechuguilla Cave – USA (13/20)

Found in New Mexico’s Carlsbad Caverns National Park, Lechuguilla Cave is one of the most scientifically important caves on the planet. With a length of 225 kilometers (140 miles), it is known for its extraordinary formations, including gypsum chandeliers, and its incredible biodiversity. Unlike most caves, the Lechuguilla Cave has been explored in an effort to uncover new microbial life, making it a hotbed of research.