Cenotes are formed by dissolution of rock and the resulting subsurface void, which may or may not be linked to an active cave system, and the subsequent structural collapse of the rock ceiling above the void. Rock that falls into the water below is slowly removed by further dissolution, creating space for more collapse blocks. Here is a beautiful cenote in the Yucantan Penisula, Mexico. Continue reading for more breathtaking places you have to visit before you die.

Bonus Video – Dean’s Blue Hole

Dean’s Blue Hole is the world’s deepest known blue hole with seawater. It plunges 202 metres (663 ft) in a bay west of Clarence Town on Long Island, Bahamas. In April 2010, William Trubridge broke a free-diving world record in the blue hole reaching a depth of 92 metres (302 ft) without the use of fins (Constant Weight Without Fins). On 14 December 2010, he swam to a depth of 101 metres on a single breath using only his hands and feet for propulsion.