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)

Natalie Portman and Tessa Thompson speak at the Marvel Studios Panel during 2019 Comic-Con International at San Diego Convention Center on July 20, 2019 in San Diego, California. (Photo by Kevin Winter/Getty Images)

A wave carrying plastic waste and other rubbish washes up on a beach in Koh Samui in the Gulf of Thailand on January 19, 2021. (Photo by Mladen Antonov/AFP Photo)

Mini-pigs perform during the presentation in Balashikha, Russia on December 19, 2018. (Photo by Maxim Shemetov/Reuters)

A man wearing a face mask walks his dog as he pulls a trolley after shopping in Beijing on February 13, 2020. The number of deaths and new cases from China's COVID-19 coronavirus outbreak spiked dramatically on February 13 after authorities changed the way they count infections in a move that will likely fuel speculation that the severity of the outbreak has been under-reported. (Photo by AFP Photo/China Stringer Network)

An Afghan driver stands amid boxes of dry food next to his damaged truck at the site of an accident near the Pakistan-Afghanistan border crossing point in Chaman, Pakistan on August 20, 2021. (Photo by AFP Photo/Stringer Network)

Festival-goers take photo inside of Spectra, a seven-story spiral walkway up to a viewing deck, at the Coachella Valley Music and Arts Festival in Indio, California, on April 17, 2022. (Photo by Valerie Macon/AFP Photo)

Ex-Pussycat Dolls singer Nicole Scherzinger and The Cuban Brothers perform at the de Grisogono party during the 71st annual Cannes Film Festival at Villa des Oliviers on May 15, 2018 in Cap d'Antibes, France. (Photo by Goff Photos)