Participants stretch their bodies as they pose for pictures before the Beijing International Marathon in Beijing, China, September 20, 2015. About 30,000 runners participated in the annual running event. (Photo by Kim Kyung-Hoon/Reuters)

Revellers from Russia parade during the Aoussou Carnival in Sousse, Tunisia July 26, 2015. (Photo by Anis Mili/Reuters)

Two visitors take pictures of autumn leaves at Rikugien Garden Tuesday, December 10, 2019, in the Bunkyo district of Tokyo. (Photo by Jae C. Hong/AP Photo)

Protesters march against the death in Minneapolis police custody of George Floyd, in the Manhattan borough of New York City, U.S., June 1, 2020. (Photo by Mike Segar/Reuters)

A local resident helps free a car that became stranded in a stretch of flooding road as Tropical Storm Helene strikes, on the outskirts of Boone, North Carolina, U.S. September 27, 2024. (Photo by Jonathan Drake/Reuters)

A woman greets a street artist at the San Fermin festival in Pamplona, northern Spain July 8, 2016. (Photo by Eloy Alonso/Reuters)

A man dressed in red-white-and-blue sits on the curb during a protest against President-elect Donald Trump, Wednesday, November 9, 2016, in Seattle's Capitol Hill neighborhood. (Photo by Ted S. Warren/AP Photo)

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)