A group of men play Myanmar's traditional sport of chinlone in Naypyitaw, Myanmar, Friday, November 18, 2016. (Photo by Aung Shine Oo/AP Photo)

Three girls weep after they view a memorial for the rapper XXXTentacion, Wednesday, June 27, 2018, in Sunrise, Fla. The rapper was gunned down in a luxury sports car last week. (Photo by Brynn Anderson/AP Photo)

British singer and actress Rita Ora performs on the stage at Sporting Summer Festival in Monaco on Tuesday, August 7, 2018. (Photo by Andrew Timms/Rita Ora Instagram)

Oakland Athletics left fielder Tony Kemp (5) catches the ball during the first inning against the Miami Marlins at RingCentral Coliseum in Oakland, California on August 22, 2022. (Photo by Stan Szeto/USA TODAY Sports)

Marcus Semien #2 of the Texas Rangers is doused with sports drink after the game against the Seattle Mariners at Globe Life Field on June 03, 2023 in Arlington, Texas. (Photo by Sam Hodde/Getty Images)

SKY SPORTS presenter Anna Woolhouse has stunned in a glamorous outfit ahead of Saturday's World Darts Championship action at Alexandra Palace in London in the last decade of December 2024. (Photo by @woolyanna1/Instagram)

A cenote is a natural phenomenon, a sinkhole in the Earth’s surface. The Yucatan Peninsula in Mexico has an estimated 7,000 cenotes because it is primarily made up of porous limestone. For millions of years, rainfall slowly ate away at the limestone and a huge system of underground caves and caverns was formed. Many filled with water from rain or from the underground water table. When the roof of a water filled cave collapses, a cenote is born. The water found in a cenote may be fresh water, salt water, or both. Structurally it may be completely open, like a lake, almost completely closed with just a small opening at the top, or somewhere in between.