Dean’s Blue Hole is a deep marine sinkhole. It plunges 663 ft from the surface of a bay of the Long Island, Bahamas. The diameter of the mouth of the hole is about 100 ft. If you go deeper the hole becomes wider. The water of the hole is so clear that you can see up to 115 ft under the water. Diving into it can be dangerous without proper precaution. In 2013, a free driver
Nicholas Mevoli died during an effort to dive
into it to set a record.