The second deepest blue hole in the world has been discovered off the coast of the Yucatan Peninsula in Mexico. The giant, underwater cavern, located in Chetumal Bay, is around 900 feet (274 meters) deep and spans an area of 147,000 square feet (13,660 square meters).
That's just shy of the record set by the world's deepest known blue hole — the Dragon Hole in the South China Sea — which was discovered in 2016 and is thought to be more than 980 feet (300 m) deep.
