On the western side of Mount Hood lies the longest glacier cave system in the contiguous United States. In 2012, these caves were mapped to a combined length of 7,166.8 feet by cave explorers Brent McGregor and Eddy Cartaya. Currently, the total passage length is hundreds of feet less. Glaciers are frozen rivers; they are always moving and changing... (Photo and caption by Josh Hydeman)

Pamukkale, Turkey, is home to these terrace pools, formed by the build-up of carbonate mineral from the warm water flowing from the thermal springs above. (Photo by Image Courtesy of Jennifer Hayes/Getty Images)

A woman takes a selfie in front of a Lunar New Year display featuring sheep at a shopping mall in Hong Kong, February 13, 2015. (Photo by Bobby Yip/Reuters)

A waxworks artist retouches one of the wax figures at the unveiling of Little Mix waxwork figures at Madame Tussauds, in London, Britain, July 28, 2021. (Photo by Peter Nicholls/Reuters)

A receptionist dinosaur robot performs at the new robot hotel, aptly called Henn na Hotel or Weird Hotel, in Sasebo, southwestern Japan, Wednesday, July 15, 2015. From the receptionist that does the check-in and check-out to the porter that’s a stand-on-wheels taking luggage up to the room, the hotel, that is run as part of Huis Ten Bosch amusement park, is “manned” almost totally by robots to save labor costs. (Photo by Shizuo Kambayashi/AP Photo)

A woman, with her face covered with colored powders, dances during the Holi Festival of Colors in Lisbon, Sunday, September 15 2013. The festival, which is mainly celebrated during the Hindu spring festival Holi in some regions of India and Nepal, has become popular among people in other communities. (Photo by Francisco Seco/AP Photo)

Colorful hot air balloons glide across the Qicai Danxia scenic area in Zhangye City, northwest China's Gansu Province on August 17, 2023. (Photo by Rex Features/Shutterstock)

Italian illusionist Arturo Brachetti perfoms in the mirrored mazes of Camera Obscura on August 06, 2024 in Edinburgh, Scotland. His show SOLO which is running at Pleasance’s EICC sees over fifty characters come to life through illusions, transformations and some magic tricks. (Photo by Jeff J. Mitchell/Getty Images)