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 red squirrel and a woodpecker having an “argument” over some nuts in a woodland near Lockerbie, Dumfries and Galloway in Johnsfield, England in September 2020. (Photo by Karen Crawford/South West News Service)

Hot air balloons in flight over Melbourne, Australia on January 24, 2022. (Photo by Rex Features/Shutterstock)

A boy plays on the glass at Thailand's first skywalk in Bangkok, Thailand on November 18, 2018. (Photo by Soe Zeya Tun/Reuters)

A dog surfs at the 6th Annual Surf City surf dog contest in Huntington Beach, California September 28, 2014. (Photo by Lucy Nicholson/Reuters)

A gaggle of goslings huddle together under the protective wing of a parent along the bank of the Deschutes River as a heavy downpour passes through Bend, Oregon, late Wednesday, April, 20, 2106 afternoon. (Photo by Ryan Brennecke/The Bulletin via AP Photo)

A US Marine feeds an orphan kitten found after a heavy mortar barrage near “Bunker Hill” during the Korean War. (Photo by Sgt Martin Riley/Getty Images). 1953

British singer-songwriter Rita Ora visits The Empire State Building on July 09, 2024 in New York City. (Photo by Dimitrios Kambouris/Getty Images for Empire State Realty Trust)