The Great Blue Hole is a massive sinkhole located just off the coast of Belize.
It is found near the center of Lighthouse Reef, a small atoll located 100 kilometers from the mainland coast and Belize City.
The sinkhole is circular in shape and is more than 300 meters wide and 123 meters deep.
The Great Blue Hole is the second largest marine sinkhole on the planet, second only after the Dragon Hole in the South China Sea
As noted by experts, the sinkhole formed during several episodes of quaternary glaciation when sea levels were much lower.
When the last Ice Age, ended some 12,000 years ago, the sea level rose, the caves flooded, the cover collapsed and the structure formed.
It is believed to be the world’s largest phenomenon of its kind.
The Great Blue Hole is part of the Barrier Reef Reserves System of Belize, Unesco World Heritage Site. The Sinkhole achieved world fame when Jacques Cousteau declared it one of the top five scuba diving sites in the world.
In November and December of 2018, researchers conducted around 20 dives into the Great Blue Gole using Aquatica’s Stingray submarine and the Roatan Institute of Deepsea Exploration’s (R.I.D.E.) Idabel submarine.
During the dives, researchers including Richard Branson and Fabien Cousteau, grandson of famous underwater explorer Jacques Cousteau, scanned and mapped the sinkhole’s interior.
Furthermore, using sonar scanning, the team produced a nearly complete three-dimensional map of the 300 meter-wide sinkhole.
But they also produced a stunning series of photographs.