President Joe Biden holds a baby as he visits a COVID-19 vaccination clinic at the Church of the Holy Communion Tuesday, June 21, 2022, in Washington. (Photo by Evan Vucci/AP Photo)

People smeared with “Gulal” or coloured powder during celebrations of Hindu spring festival “Holi” in Hyderabad, India on March 7, 2023. (Photo by Noah Seelam/AFP Phoot)

An Iraqi man sells dried fish ahead of Eid al-Fitr, which marks the end of the Muslim holy fasting month of Ramadan, in Basra on April 8, 2024. (Photo by Hussein Faleh/AFP Photo)

College students play with coloured powder to celebrate the festival of Holi, near Jantar Mantar in New Delhi on March 7, 2023 (Photo by Press Trust of India)

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.

An Indian Sadhu, or Hindu holy man, sits for a community feast at the Sangam, the confluence of the Rivers Ganges, Yamuna and mythical Saraswati, during the annual month-long Magh Mela religious fair in Allahabad, India, Friday, January 16, 2015. Hundreds of thousands of devout Hindus are expected to take holy dips at the confluence during the astronomically auspicious period of over 45 days celebrated as Magh Mela. (Photo by Rajesh Kumar Singh/AP Photo)

A woman carries a stone cross in a cemetery in the village of Copaciu, southern Romania, on May 2, 2013. As part of a Holy Week tradition, Romanians visit, on Maundy Thursday, the graves of their loved ones, light fires and share food with community members in memory of the departed. Orthodox worshipers celebrate Easter on May 5. (Photo by Andreea Alexandru/ Mediafax)