Deans Blue Hole, extending down to a vast 663ft, is thought to be the world’s deepest ocean blue hole. Dean’s Blue Hole is located on the tropical Long Island of the Bahamas and is truly a place of wonder for snorkelers and scientists like. Once you enter the shallow waters off the white sand beach, only about 5 ft., you are just a few kick strokes away from the drop-off. The Hole is almost completely surround by cliffs bases which keeps currents out and makes for easy, relaxing snorkeling. The hold itself is not the only attraction here though, keep your eyes peeled for tropical fish, turtles, and even the occasional dolphins who are known to show up! If you are an avid snorkeler, Dean’s Blue Hole is a must-see location on your snorkeling travel itinerary.