Genko Stoykov fires a rifle as he and other men prepare for the traditional “Horo” dance on Epiphany Day in the icy winter waters of the Tundzha river on January 6, 2022 in Kalofer, Bulgaria. As part of the tradition, a priest throws a cross in the river and it is believed that the one who retrieves it will be healthy throughout the year. Today, cultures throughout Christendom mark the Feast of the Epiphany, when Jesus was revealed to the Magi as God incarnate. (Photo by Hristo Rusev/Getty Images)

A woman looks at a swimmer getting herself warm after the annual Christmas winter swimming competition in the Vltava river in Prague December 26, 2014. (Photo by David W. Cerny/Reuters)

A visitor falls down as they run away from a wave caused by a tidal bore which surged past a barrier on the banks of Qiantang River, in Hangzhou, Zhejiang province, China, October 28, 2015. (Photo by Reuters/China Daily)

Wizz Air's Airbus A-321 flying along the Danibe river during an air show in Budapest, Hungary, May 1, 2016. (Photo by Laszlo Balogh/Reuters)

A cow covered with foam scavenges in the waste left on the banks of the polluted Yamuna river in New Delhi on October 10, 2020. (Photo by Sajjad Hussain/AFP Photo)

A man bathes in an ice hole in the Neva River St. Petersburg, Russia, Wednesday, February 10, 2021. The temperature in St. Petersburg is –15C ( 5 °F). (Photo by Dmitri Lovetsky/AP Photo)

An aerial view shows local residents visiting a river side park in Taipei during the Lunar Mew Year on February 19, 2021. (Photo by Sam Yeh/AFP Photo)

Hot-air balloons float over the Oka River during the Russian Sky International Balloon Festival in Ryazan Region, Russia on July 26, 2021. (Photo by Alexander Ryumin/TASS)