Date: 1/4/2007
Divers discovered what they claim is the worldâs largest submerged cave system – effectively an underground river – beneath Mexicoâs Yucatán Peninsula. Stephen Bogaerts and Robbie Schmittner spent four years exploring whether the Sac Actun system links to other cave networks before they made the final connection that revealed a single system that is 95 miles (153 km) long. The two divers entered the system separately and worked their way through huge chambers and tiny tunnels to meet up at the connection point they had always believed they would find. It took some 500 dives of several hours each for them get to the connection point.