Great Blue Hole

The Great Blue Hole (English: great blue hole ) is a round underwater sinkhole off the coast of the Central American country of Belize. It is located near the center of the Caribbean Lighthouse Reef, about 70 kilometers from the city of Belize City. From the air, it can be seen as a striking dark blue, round face of the deep water in the shallow, turquoise waters of the Caribbean.

The Great Blue Hole is roughly circular in shape, measuring about 300 meters in diameter and up to 125 meters deep. At the end of the last ice age it originated in the limestone layers and forms an entrance to an underground cave system, which was flooded by rising sea levels. In about 90 feet of water is a hydrogen sulphide-containing thermocline.

The Great Blue Hole was declared a National Monument in 1996 and since then, along with other parts of the reef system Belize Barrier Reef, a UNESCO World Heritage Site. In June 2009, the Belize Barrier Reef UNESCO has been added to the list of endangered World Heritage Site.

Underwater World

Opened on the south wall of the Blue Hole in about 35 to 40 meters depth for experienced divers the underground cave system. Geologic particular interest is a gallery in the rock wall on which were formed before dropping the limestone formation below sea level numerous stalactites and stalagmites sporadically. Stalactites were measured with up to eight meters in length and approximately two meters in diameter.

Through a TV movie of the French marine explorer Jacques -Yves Cousteau, the Great Blue Hole is considered as the most famous diving place in Belize. Divers Calypso withdrawals at that time of about 50 meters depth a 2.80 -meter-long stalactite.