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)

People visit the artwork titled Seven Magic Mountains by artist Ugo Rondinone, Wednesday, May 11, 2016, near Jean, Nev. The artwork was recently completed in the desert south of Las Vegas. (Photo by John Locher/AP Photo)

The Knights of Middle England equestrian stunt display team perform ahead of the first match on July 13, 2024. The British Beach Polo Championships, or “sand polo”, returns to the exclusive Sandbanks peninsula near Poole, Dorset. Spectators can appreciate the horsemanship, speed and gladiatorial nature of polo at the largest beach polo event in the world. (Photo by Max Willcock/Bournemouth News)

The Boston Celtics dancers perform during the second quarter of the game between the Boston Celtics and the Miami Heat at TD Garden in Boston, Massachusetts on December 2, 2024. (Photo by Winslow Townson/USA Today Sports)

October 25, 2009; London,UK; The mascot for the Tampa Bay Buccaneers watches a cheerleader during the NFL International Series game against the New England Patriots at Wembley Stadium. (Photo by David Wilkinson/Offside Sports)

A model walks during the Black Tape Project fashion show at New York Fashion Week Fall 2024 powered by Art Hearts Fashion at The Angel Orensanz Foundation on February 11, 2024 in New York City. (Photo by Arun Nevader/Getty Images for Art Hearts Fashion)

Yalena Leuliette, 7, of Greenbelt, Md., throws seeds from a cattail plant up in the air as she plays while visiting the Kenilworth Aquatic Gardens in northeast Washington, on Sunday, August 9, 2015. Leuliette visits the public garden with her parents a few times a year. (Photo by Jacquelyn Martin/AP Photo)

Girls make a heart sign as the sun sets over the Mediterranean Sea coastline in Beirut, Lebanon, Friday, July 14, 2023. (Photo by Hassan Ammar/AP Photo)