A tourist walks inside the Ice Palace glacier hollow at Hintertux glacier, located at around 3250 meters above sea level, in Zillertal, Austria, 02 March, 2016. The hollow's temperature remains constant at 0 degrees Celsius, in summer and winter alike, and is also used by the University of Innsbruck for scientific research projects. (Photo by Lisi Niesner/EPA)

Pro-Russian rebels stand near a monument during a ceremony to honour the World War Two defenders of Donetsk from Nazi forces, in Donetsk, in this September 8, 2014 file photo. (Photo by Marko Djurica/Reuters)

Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

A service member of the Ukrainian armed forces is seen at fighting positions on the line of separation from pro-Russian rebels in Donetsk region, Ukraine on April 10, 2021. (Photo by Oleksandr Klymenko/Reuters)

Pro-democracy protesters dressed in traditional Thai costumes take part in an anti-government rally in Bangkok on October 14, 2020. (Photo by Jack Taylor/AFP Photo)

Tam Nakano and Maika compete during the Women's Pro-Wrestling “Stardom” at Korakuen Hall on October 17, 2021 in Tokyo, Japan. (Photo by Etsuo Hara/Getty Images)