People use snowshoes during a tour of the Great Kemeri Bog, Latvia, October 17, 2015. The Kemeri bog is more than 8,000 years old and is one of the largest dry moss swamps in the Baltics. A more than decade-long joint restoration of the bog by the European Union and the Latvian government helped the bog recover its high moss marshes, damp black alder forests, floodplain meadows and seaside lakes – features now considered rare in Europe due to industrialisation. (Photo by Ints Kalnins/Reuters)

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.

Alex Prager is an American art photographer and filmmaker based in Los Angeles. Her photographs primarily use staged actors, models and extras to create “meticulously designed mise en scène”, often described as film-like and hyperreal. “Alex Prager: Silver Lake Drive” is at the Photographers’ Gallery, London, 15 June – 14 October 2018. Here: The Big Valley, Susie and Friends, 2008. (Photo by Alex Prager Studio/Lehmann Maupin Gallery)

Nobby the polar bear cools down as he plays in a lake at the Yorkshire Wildlife Park in Doncaster, England, Friday June 17, 2022. A blanket of hot air stretching from the Mediterranean to the North Sea is giving much of western Europe its first heat wave of the summer, with temperatures forecast to top 30 degrees Celsius (86 degrees Fahrenheit) from Malaga to London on Friday. (Photo by Danny Lawson/PA Wire via AP Photo)

A pilgrim holds up the cross after it was thrown by an Orthodox priest into the water, during an epiphany ceremony to bless the sea, on the southeast resort of Ayia Napa, Cyprus, Friday, January 6, 2023. By tradition, a crucifix is cast into the waters of a lake or river, and it is believed that the person who retrieves it will be freed from evil spirits and will be healthy through the year. (Photo by Petros Karadjias/AP Photo)

An open water swimmer surfaces as she enjoys a socially-distanced dawn swim after breaking the ice on the surface of a lake near Scunthorpe, northern England, January 9, 2021. Faced by a sharp rise in coronavirus infections, driven by the new strain, England entered a strict lockdown on January 5, 2021, with schools and non-essential shops closed for at least six weeks after previous measures failed to halt the steep rise in cases. (Photo by Lindsey Parnaby/AFP Photo)

Ethnic Entha fishermen display placards during a protest against the military coup on Inle Lake, Taunggyi, Myanmar Thursday, February 11, 2021. Large crowds demonstrating against the military takeover in Myanmar again defied a ban on protests Thursday, even after security forces ratcheted up the use of force against them and raided the headquarters of the political party of ousted leader Aung San Suu Kyi a day earlier. (Photo by Aung Ko San/AP Photo)