Comet Enthusiast

The Great Blue Hole, a World Heritage site,  is a large underwater sinkhole off the coast of Belize. Jacques Cousteau took the Calypso and his one-man submarines into the hole in 1972 to examine stalactites suspended from overhanging walls. The Great Blue Hole is surrounded by shallow water of Lighthouse Reef Atoll, a nearly perfect circle in the middle of a shallow reef.