Street fighting in Berlin between Government troops and Spartacists, during the Spartacist uprising which followed Germany's defeat in World War I. (Photo by Keystone/Getty Images). 1919

Egyptian President Hosni Mubarak speaks to the media after talks with German Chancellor Angela Merkel at the Chancellery on April 23, 2008 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)

Dancers of the Friedrichstadt-Palast from the show “THE WYLD” pose during a promotional photocall in front of the Brandenburg Gate in Berlin, Germany, June 25, 2015. The 10.6 million euro ($13.5 million) show is the largest production budget in the 95-year history of Friedrichstadt-Palast. (Photo by Hannibal Hanschke/Reuters)

A wax figure depicting Jennifer Lopez by wax museum Madame Tussauds dressed in a new set of clothes attracts the attention of pedestrians during a press event at a beach bar in Berlin,†Germany, August 21, 2015. (Photo by Jens Kalaene/EPA)

Actors and dancers perform during the press rehearsal for the “ARISE Grand Show” at the Friedrichstadt-Palast theater in Berlin, Germany, 15 September 2021. Premiere of the show is scheduled for 16 September and will amaze vistors with “extravagant costumes, breathtaking stage sets and artistic excellence” until February 2022 as the theater promises on its website. (Photo by Filip Singer/EPA/EFE)

Spain supporters celebrate as Spain's Nico Williams scores the opening goal in Madrid, Spain, July 14, 2024 during the screening of the final match between Spain and England at the Euro 2024 soccer tournament in Berlin Germany. (Photo by Andrea Comas/AP 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.

Germany fans cheer after the 2-0 goal for Germany during the UEFA Euro 2024 football match between Germany and Hungary at the public football viewing area in Berlin, Germany on June 19, 2024. (Photo by Jörg Carstensen/AFP Photo)