The Great Blue Hole: Belize

Known for its circular shape and strikingly deep blue color, the Great Blue Hole is a 1,000-foot-wide sinkhole in the middle of Belize's Lighthouse Reef. While an aerial shot is enough to convince anyone of its beauty, scuba divers are the ones who get to experience the wonders that lie beneath—massive limestone stalactites and stalagmites that formed during the last glacial period.