Analysis of the sediment in Belize’s Great Blue Hole shows a concerning trend. Blue holes, the name for collapsed limestone ...

As Kakuk and I emerge from the hydrogen sulfide into the black water below ... cove on Long Island, Dean’s Blue Hole—Earth’s deepest known underwater cave—plunges more than 600 feet ...

A sample drilled from the bottom of the Great Blue Hole has uncovered 5,700 years of history. The underwater sinkhole, located off the coast of Belize in Central America, is one of the world's most ...