The mysterious 'Mayan world' inside the world's largest underground cave
Researchers of the Gran Acuifero Maya (GAM) Aquifer Discovery Project have discovered the world's largest underground cave system called Sac Actun in the Yucatán PeninsulaDiscover the largest underwater cave on the planet
Archaeologists find the largest underwater cave in the waters off the southeastern Yucatan Peninsula of Mexico, the International Business Times reported on January 17.