A black gibbon is seen in a cage before being released into the wild by Indonesian nature conservation agency (BKSDA) in Jantho forest, Aceh province on August 26, 2021. (Photo by Chaideer Mahyuddin/AFP Photo)

A black bear cub performs for its mum at the Pocosin Lakes National Wildlife park in North Carolina, US in January 2022. (Photo by Jennifer Hadley/Animal News Agency)

Scarlett Johansson, Florence Pug, Rachel Weisz and David Harbour star in the action spy thriller “Black Widow”. Pictured: English actress Florence Pugh as Yelena. (Photo by Splash News and Pictures)

American singer-songwriter Katy Perry in the second decade of June 2024 posed in a white bra top with heavy black metallic leg armour to announce her new single Woman’s World. (Photo by Katy Perry/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.

A tourist splashes water on the frozen Songhua River on December 18, 2023 in Harbin, Heilongjiang Province of China. The water immediately freezes into ice in the frigid air. (Photo by VCG/VCG via Getty Images)

Children take part in the “Carnavalito” children's parade during the Blacks and Whites Carnival in Pasto, Colombia, on January 2, 2018. (Photo by Juan Barreto/AFP Photo)

A participant dances as approximately 70,000 people from all over the world gathered for the annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. on August 29, 2017. (Photo by Jim Urquhart/Reuters)