The Great Blue Hole is a large submarine sink-hole off the coast of Belize. It lies near the centre of Lighthouse Reef, a small atoll 70 km mi) from the mainland and Belize City. The Great Blue Hole is a part of the larger Belize Barrier Reef.
Caye Caulker is a small limestone coral island off the coast of Belize in the Caribbean Sea measuring about 5 miles by less than 1 mile. The town on the island is known by the name Caye Caulker Village.