A female black lemur (Eulemur macaco), looks at a camera in its enclosure at Bioparc Fuengirola in Fuengirola, near Malaga, southern Spain, February 8, 2017. (Photo by Jon Nazca/Reuters)

Australian professional basketball player Liz Cambage shows off her extensive tattoo collection in a tiny black bikini while having a smoke on the beach in Miami on April 7, 2021. (Photo by The Mega Agency/Profimedia)

Pope Francis looks at an acrobat of the “Black Blues Brothers” performing during his weekly general audience in St. Peter's Square at The Vatican, Wednesday, Nov. 30, 2022. (Photo by Andrew Medichini/AP Photo)

A serviceman of Ukraine's coast guard mans a gun on a patrol boat as a cargo ship passes by in the Black Sea, amid Russia’s attack on Ukraine, on February 7, 2024. (Photo by Thomas Peter/Reuters)

On the afternoon of the June 12, 2025, a couple wearing black dresses took wedding photos at Dadaepo Beach in Saha-gu, Busan. (Photo by Kim Dong-hwan)

A Kashmiri Muslim woman balances on a water pipe before collecting water at Dasilpora village on March 22, 2018. World Water Day is held annually on 22 March as a means of focusing attention on the importance of freshwater and advocating for the sustainable management of freshwater resources. (Photo by Tauseef Mustafa/AFP Photo)

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.

Police officers react as they attempt to detain a protestor near the entrance to Downing Street, during an anti-racism demonstration in London, on June 3, 2020, after George Floyd, an unarmed black man died after a police officer knelt on his neck during an arrest in Minneapolis, USA. Londoners defied coronavirus restrictions and rallied on Wednesday in solidarity with protests raging across the United States over the death of George Floyd, an unarmed black man who died during an arrest on May 25. (Photo by Daniel Leal-Olivas/AFP Photo)