Great Blue Hole

The Great Blue Hole is a massive underwater sinkhole off the coast of Belize which extends 125 meters into the Earth’s crust. It lies near the center of Lighthouse Reef, a small atoll 100 kilometres (62 miles) from the mainland of Belize City.

The hole is circular in shape, 318 m across and 124 m deep. Scuba divers and snorkelers have been cruising the surface waters for decades, but few have dared to venture deeper and explore what lies beyond the blackness.

In the winter of 2018, a crew from Aquatica Submarines which included, Sir Richard Branson, Fabien Cousteau and Erika Bergman ventured to the bottom of the Great Blue Hole. Their mission was to create a 3D map of the sinkhole’s interior, but along the way, they made some unexpected discoveries: fascinating geological formation: caves upon caves of hanging stalactites and otherworldly beautiful passages in its depth.

They also found the usual suspects: reef sharks, turtles, and giant corals. But as they pushed 90 meters, life started to vanish. The culprit was a thick layer of toxic hydrogen sulfide spanning the width of the entire sinkhole like a floating blanket.