Vietnam’s Son Doong cave, the largest in the world, could hold a 40-story skyscraper inside. The pristine ecosystem has its own river and jungle. Despite its size, Son Doong wasn’t discovered until 1991. It was lost again for nearly two decades and was fully explored for the first time in 2009. (Photo by Jason Speth/HuffPost)

A camel is pictured in front of the Saturn tracking complex at the Russian-leased Baikonur cosmodrome in Kazakhstan on October 9, 2018. An astronaut and cosmonaut are due to travel to the ISS on October 11 aboard a Russian Soyuz MS-10 spacecraft from the Baikonur Cosmodrome in Kazakhstan. (Photo by Kirill Kudryavtsev/AFP Photo)

A firefighter jumps over a fence while fighting the Palisades Fire in the Pacific Palisades neighborhood of Los Angeles, Tuesday, January 7, 2025. (Photo byh Ethan Swope/AP Photo)

Manar Abu Dhabi presents its second public light art exhibition on November 17, 2025. Organized by the Department of Culture and Tourism. KAWS, located at Souq Al Mina, Abu Dhabi. (Photo by Victor Besa/The National)

Visitors look on as a man (front) inserts two live snakes through his nose and mouth during a performance at an amusement park to celebrate the 65th anniversary of the founding of the People's Republic of China and the 7-day national day holiday, in Jinhua, Zhejiang province October 1, 2014. (Photo by Reuters/Stringer)

A penitent called “Morion” checks his mobile phone in Mogpog town on Marinduque island in central Philippines April 14, 2014. During the annual festival, masked and costumed penitents called “Moriones” dress in attire that is the local interpretation of what Roman soldiers wore during biblical times. Holy Week is celebrated in many Christian traditions during the week before Easter. (Photo by Erik De Castro/Reuters)

A boy holds his mother's leg as he cries in front of their damaged house after a strong 6.6 magnitude earthquake at Longmen village, Lushan county in Ya'an, Sichuan province. (Photo by Jason Lee/Reuters)

Russia's synchronised swimming duet Aleksandr Maltsev (L) and Darina Valitova compete in the Mixed Duet Technical preliminary during the synchronised swimming competition at the 2015 FINA World Championships in Kazan on July 25, 2015. (Photo by Christophe Simon/AFP Photo)