S1 E3 Stone Under Earth and Water - Caving with Bill Stone

I doubt there is a person on the planet who has spent more time underground than Dr Bill Stone PhD. By the age of 19, Bill was involved in major deep caving expeditions to Mexico, and soon after that he was leading his own trips underground. When he reached water in the depths of Sistema Huautla, he wasn't deterred. Instead, in only a way Bill Stone can, he build his own diving system from the ground up and went on to discover many more hundreds of meters of cave passage in an epic expedition...