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)

Officer cadets at Sandhurst military academy celebrate completing the Sovereign's Parade which see's them become commissioned officers in the army on April 11, 2025. The parade marks the completion of 44 weeks of intensive training for the Officer Cadets of Commissioning Course 242, all of whom will officially hold HM the King's Commission as of the stroke of midnight on the day of the parade. In addition, there are 26 international cadets from 18 countries. (Photo by Times photographer Richard Pohle)

A house that was slammed off its foundation by Hurricane Isabel sits precariously on the beach one month after it hit Rodanthe, North Carolina October 18, 2003. (Photo by Rick Wilking/Reuters)

Revellers hit the booze cruise in the Croatian port city of Split on August 11, 2023. The hot new party town for Brits. Boat Party booze cruise with Split after dark. (Photo by Darren Fletcher)

Mike De Paola, founding director of TW Fine Art, is seen near an art installation at “Feltz Bagels”, a bagel bakery made entirely from felt, at TW Fine Art in Montauk, New York, U.S. August 11, 2023. (Photo by Roselle Chen/Reuters)

People and security members run away as Kurdish animal rights activists release a bear into the wild after rescuing bears from captivity in people homes, in Dohuk, Iraq on February 11, 2021. (Photo by Ari Jalal/Reuters)

A woman runs through the early morning mist on Hampstead Heath on September 30, 2011 in London, England. Much of the UK is enjoying a spell of unseasonably hot weather which is expected to last into next week. (Photo by Dan Kitwood/Getty Images)

An anti-government protester wearing a Guy Fawkes mask stands with a shield near flames from molotov cocktails thrown at a water cannon by anti-government protesters during riots in Caracas in this April 20, 2014 file photo. (Photo by Jorge Silva/Reuters)