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.

Chinese conglomerate Tiens Group employers take photos while waiting to be served Paella in Madrid, Spain, Friday, May 6, 2016. The billionaire founder of Chinese conglomerate Tiens Group is treating 3,000 of his best salespeople to a traditional Spanish paella meal in a free Madrid trip that also includes a bullfight and a tour of King Felipe VI's Royal Palace. The smiling salespeople washed down their heaping plates of paella with sangria Friday at a mass spread of picnic tables in a riverside park during the event footed by Li Jinyuan and organized by China's U Tour travel company. (Photo by Paul White/AP Photo)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

«Sharon Wild (from the series The Valley)», 2001. Larry Sultan grew up in California’s San Fernando Valley, which was a source of inspiration for a number of his projects. His series The Valley (2004) addresses the use of ordinary homes as sets for pornographic films, and asks why the ideal of middle-class domesticity lends itself to this most curious form of cultural appropriation. (Photo by Larry Sultan)

Ornamental chicken breeding clubs have emerged in Indonesia, Thailand, North America and even European countries such as the UK and France. Malaysia is however the epicenter of this cultural phenomenon. These chickens are prized for their build, size, behavior and showmanship by their owners and competitions or beauty contests as they are often described are held almost every week in at least one village in Malaysia. Judges sit around a square table inspecting each chicken for a few minutes trying to determine a champion specimen in its own weight class based on its stance, temperament and physical assets like wings, tails and comb. The walk or strut by an ornamental chicken in a beauty contest, much like a runway model, constitutes a large part of the scoring system. (Photo by Ernest Goh/2013 Sony World Photography Awards)

A street vendor sells Dalgona candy from the Korean Netflix series “Squid Game” at a Dalgona shop in Seoul, South Korea, October 1, 2021. (Photo by Heo Ran/Reuters)

Ice Road Truckers is a reality television series that premiered on History on June 17, 2007. It features the activities of drivers who operate trucks on seasonal routes crossing frozen lakes and rivers in remote Arctic territories in Canada and Alaska. Later series were focused on Alaska's improved but still remote Dalton Highway which is mainly snow covered solid ground.