What is Under Us?
A team of explorers retrace Joseph Berger, Marc Jouffray, Bouvet, and Ruix de Arcaute's adventure  almost 60 years later. They first discovered
Gouffre Berger in 1953. It is currently the 28th deepest cave on earth and the fourth largest in France. 
Can you imagine digging and finding something like this?

Source posted by Julia