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)

Jordanian soldiers pose after the opening ceremony of eighth annual Warrior Competition at the King Abdullah Special Operations Training Center (KASOTC) in Amman, Jordan, May 2, 2016. Twenty Seven Teams from Eleven countries are participating in a competition to test their military skills. (Photo by Muhammad Hamed/Reuters)

Camera trapper Xavier Hubert-Brierre put this large mirror on the side of a road through the jungle in Gabon and left a camera there to record how the animals would respond to their own reflections. A silverback gorilla thought it was seeing another silverback and responded by trying to scare off the potential challenger… (Photo by Xavier Hubert-Brierre/Johns Hopkins University Press)

Big waves approach the beach of Nazare, Portugal, Tuesday, March 26, 2024. The high waves were caused by strong winds at one of the world's most popular surf spots. (Photo by Michael Probst/AP Photo)

A tourist visits an ocean park during the International Day for Biological Diversity on May 22, 2024 in Handan, Hebei Province of China. May 22 marks the 24th International Day for Biological Diversity. (Photo by Hao Qunying/VCG via Getty Images)

Kinga Drozdz of Team Poland reacts against Xufeng Zou of Team China during the Women's Sabre Category A quarterfinals on day six of the Paris 2024 Summer Paralympic Games at Grand Palais on September 03, 2024 in Paris, France. (Photo by Steph Chambers/Getty Images)

Polling station officials dressed as traditional Balinese performers vote in Badung regency on the Indonesian island of Bali December 9, 2015 in this photo taken by Antara Foto. Around 100 million Indonesians were expected to go to the polls on Wednesday in many parts of the country to elect heads of local government. (Photo by Wira Suryantala/Reuters/Antara Foto)

The “Escape Velocity” moving sculpture by artist group Poetic Kinetics looms over Coachella festivalgoers on the Empire Polo Field, on the first day of the 2014 Coachella Music and Arts Festival in Indio, California, on April 11, 2014. (Photo by Chris Pizzello/Invision)