Members of Brighton Swimming Club brave the early morning temperature to take a dip in the sea east of the pier on January 5, 2022. The club, founded in 1860, is the oldest in England. (Photo by Simon Dack/Alamy Live News)

Team Japan competes during the team free preliminaries of artistic swimming at the 19th FINA World Championships in Budapest, Hungary, Wednesday, June 22, 2022. (Photo by Anna Szilagyi/AP Photo)

This photo taken on November 7, 2023 shows winter swimming enthusiasts taking photos at Beiling Park after snowfall in Shenyang, in China's northeastern Liaoning province. (Photo by AFP Photo/China Stringer Network)

Australia’s Hannah Fredericks competes in the women’s 200m backstroke heats during the Australian Swimming Trials at the Brisbane Aquatic Centre on June 13, 2024. (Photo by David Gray/AFP Photo)

This aerial view shows youths swimming to cool off in the waters of Iraq's Euphrates river during a heatwave, in the district of al-Hindiyah east of Karbala on June 7, 2024. (Photo by Karar Jabbar/AFP Photo)

A person dressed as Santa Claus jumps into the sea during the Copa Nadal (Christmas Cup) swimming race in Barcelona, Spain on December 25, 2024. (Photo by Bruna Casas/Reuters)

Looking for a reason to visit the Philippines? This mermaid school should do the trick. No, seriously, there’s an actual school that will teach you how to be a mermaid. It’s called the Philippines Mermaid Swimming Academy. (Photo by Philippine Mermaid Swimming Academy/Exclusivepix Media)

National Geographic photographer Steve Winter has spent most of his adult life shooting wild cats. Photo: A 14-month-old cub, cooling off in a pond, is riveted by a deer that appeared near the shore. Tigers are powerful swimmers; they can easily cross rivers four to five miles wide and have been known to swim distances of up to 18 miles. (Photo by Steve Winter/National Geographic)