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)

Models pose for a group photograph outside the Victoria's Secret shop on New Bond Street in central London, December 1, 2014. The 2014 Victoria's Secret Fashion Show will be held in London on Tuesday. (Photo by Andrew Winning/Reuters)

A participant dressed up in a costume attends the 2021 Prague Comic Con in Prague, Czech Republic, October 16, 2021. (Photo by David W. Cerny/Reuters)

Natalie Dormer attends the mtvU Fandom Awards at MTV Fan Fest at Comic-Con, July 24, 2014, in San Diego. (Photo by Jordan Strauss/Invision for MTV/AP Images)

Twin brothers Keith (L) and Deano Stapleton (R) interact with one another as people gather to witness the winter solstice on December 21, 2022 in Newgrange, Ireland. Crowds are gathering at Newgrange in Co Meath, this morning for the winter solstice – the astronomical phenomenon that marks the shortest day and the longest night of the year. Newgrange is a Stone Age (Neolithic) monument in the Boyne Valley, County Meath, it is the jewel in the crown of Ireland's Ancient East and was constructed approximately 5,200 years ago (3,200 B.C.) which makes it older than Stonehenge and the Great Pyramids of Giza. (Photo by Charles McQuillan/Getty Images)

Gunther Holtorf, a 75-year-old former airline CEO who has driven more than 900,000 kilometers over the past two decades, doesn't care if you remember his travels. But you better respect Otto, his G Wagon that will be placed in a museum if it makes it through this final leg.

US freestyler, gold medalist Mcrae Williams competes during the men' s SlopeStyle (SS) finals at the FIS Snowboard and Freestyle Ski World Championships 2017 in Sierra Nevada on March 19, 2017. (Photo by Albert Gea/Reuters)