Mr Lordi aka Tomi Petteri Putaansuu of the Finnish hard rock band Lordi gets the second jab of his Covid-19 vaccination from nurse Paula Ylitalo (R) in Rovaniemi, Finland, on August 1, 2021, amid the novel coronavirus / COVID-19 pandemic. (Photo by Jouni Porsanger/Lehtikuva/AFP Photo)

A Sadhu or a Hindu holy man sits on the banks before taking a holy dip at Sangam, the confluence of the Ganges and Yamuna rivers with the mythical, invisible Saraswati river, during the “Maha Kumbh Mela”, or the Great Pitcher Festival, in Prayagraj, India, on January 13, 2025. (Photo by Adnan Abidi/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.

Shephen Shine, 27, who lost a leg when serving in Iraq in 2007, is tattood with a regimental tattoo reading “Their Sacrifice – Our Freedom” during the Ink For Heroes event on June 18, 2011 in Catterick, England. Ink For Heroes is a charity event to raise money and awareness of the soldiers that get injured during service, with all proceeds going to both “Help The Heroes” and “The British Legion”. Injured soldiers can also get tattooed for free during the event. (Photo by Bethany Clarke/Getty Images)

Dancers from the Yarrabah community perform during the Laura Aboriginal Dance Festival on June 18, 2011 in Laura, Australia. The Laura Aboriginal Dance Festival is a celebration of aboriginal dance and culture that takes place Biennially in Cape York Peninsula at the site of a traditional Bora ground that is sacred to the aboriginal community and surrounded by some of the oldest rock art in the world. Over 5000 visitors attend the festival, offering a unique insight into the community and providing an opportunity to spread cultural traditions to new generations. The festival takes place June 17-19. (Photo by Mark Kolbe/Getty Images for Tourism Queensland)

Residents (R to L) Luiza, Janubie, Leiticia and Lucas sit beneath an overpass near their houses in an impoverished area in the unpacified Complexo da Mare slum complex, one of the largest “favela” complexes in Rio, on March 18, 2014 in Rio de Janeiro, Brazil. (Photo by Mario Tama/Getty Images)

Brazil's tallest teen is set marry her beau – despite him being over a foot smaller than her. Elisany da Cruz Silva (18) is a staggering 6ft 8ins (206 cm) tall while her compact fiancee Francinaldo da Silva Carvalho is only 5ft 4ins (162 cm). Despite a massive 1ft 4ins between them, Francinaldo had no problem increasing the distance by dropping to one knee after a romantic stroll along the beach. (Photo by Barcroft Media)

Kendall Jenner uses her cellular device during Kanye West's Yeezy Season 3 Collection presentation and listening party for the “The Life of Pablo” album during New York Fashion Week February 11, 2016. (Photo by Andrew Kelly/Reuters)