Largest Underwater Caves (Total Surveyed Passage) Sistema Ox Bel Ha, Tulum Mexico: 134, 048 meters with a maximum depth of 110 feet Sistema Sac Actun, Akumal, Mexico: 61,941 meters with a maximum depth of 82 feet Sistema Nohoch Nah Chich, Akumal, Mexico: 61,143 meters with a maximum depth of 235 feet Cenote Dos Ojos, Akumal, [...]