Krubera Cave is the deepest known cave on Earth. It is located in the Arabika Massif of the Gagrinsky Range of the Western Caucasus, in the Gagra district of Abkhazia, a breakaway region of Georgia.
A pro-democracy demonstrator fights with a Soviet soldier on top of a tank parked in front of the Russian Federation building on August 19, 1991, after a coup toppled Soviet President Mikhail Gorbachev. The same day, thousands in Moscow, Leningrad, and other cities answered Russian Republic President Boris Yeltsin's call to raise barricades against tanks and troops. (Dima Tanin/AFP/Getty Images)
Members of the 1st Tennessee wait to take part in in a demonstration of a battle during ongoing activities commemorating the 150th anniversary of the Battle of Gettysburg, Friday, June 28, 2013, at at Bushey Farm in Gettysburg, Pa. Union forces turned away a Confederate advance in the pivotal battle of the Civil War fought July 1-3, 1863, which was also the war's bloodiest conflict with more than 51,000 casualties. (Photo by Matt Rourke/AP Photo)
New York City mayoral candidate Maya Wiley hula hoops while campaigning on June 20, 2021 in the Bedford Stuyvesant neighborhood of Brooklyn, New York. The primary election for New York City mayor will be held on June 22, 2021. (Photo by Andrew Lichtenstein/Corbis via Getty Images)
American model Bella Hadid poses as she arrives for the screening of the film “Tre Piani” (Three Floors) at the 74th edition of the Cannes Film Festival in Cannes, southern France, on July 11, 2021. (Photo by Reinhard Krause/Reuters)
A United States Border Patrol agent on horseback tries to stop a Haitian migrant from entering an encampment on the banks of the Rio Grande near the Acuna Del Rio International Bridge in Del Rio, Texas on September 19, 2021. The United States said Saturday it would ramp up deportation flights for thousands of migrants who flooded into the Texas border city of Del Rio, as authorities scramble to alleviate a burgeoning crisis for President Joe Biden's administration. (Photo by Paul Ratje/AFP Photo)
A participant tests his motorcycle ahead of the launch of the Rally of Morocco 2021, in the desert Zagora region, on October 7, 2021. The rally will be held from October 8 to 13, 2021. (Photo by Fadel Senna/AFP Photo)
People walk among yellowish trees at Kolomenskoye Park during autumn season in Moscow, Russia on October 03, 2021. (Photo by Sefa Karacan/Anadolu Agency via Getty Images)