Opera singers perform in the pool “AquAria PALAOA” during a rehearsal at the swimming pool Neukoelln on April 27, 2011 in Berlin, Germany. The premiere of the underwater opera AquAria PALAOA is on May 1st. (Photo by Andreas Rentz/Getty Images)

Over 1000 New Year revellers, many in fancy dress, braved freezing conditions in the River Forth in front of the Forth Rail Bridge during the annual Loony Dook Swim on January 1, 2012 in South Queensferry, Scotland. Thousands of people gathered last night to see in the New Year at Hogmanay celebrations in towns and cities across Scotland. (Photo by Jeff J. Mitchell/Getty Images)

Gold Medalist Kristof Milak of Hungary during the medals ceremony of the 200m Butterfly final on day five of the swimming competition of the Tokyo 2020 Olympic Games at Tokyo Aquatics Centre on July 28, 2021 in Tokyo, Japan. (Photo by Aleksandra Szmigiel/Reuters)

People dressed as mermaids and mermen take part in the group swim during the MerMagic Convention at the Freedom Aquatic & Fitness Center in Manassas, Virginia on March 4, 2023. The event bills itself as the “World's Largest Mermaid Convention”. (Photo by Joseph Prezioso/AFP Photo)

Ukrainians swim in an ice hole as part of the celebration of the Epiphany in Kiev, Ukraine, Monday, January 19, 2015. Orthodox believers celebrate the holiday of the Epiphany on Jan. 19, and traditionally bathe in holes cut through thick ice on rivers and ponds to cleanse themselves with water deemed holy for the day. (Photo by Sergei Chuzavkov/AP Photo)

Chinese women wear face-kinis as they walk in to the water to swim at the beach on August 20, 2014 in the Yellow Sea in Qingdao, China. The locally designed mask is worn by many local women to protect them from jellyfish stings, algae and the sun's ultraviolet rays. (Photo by Kevin Frayer/Getty Images)

A girl jumps over a campfire while celebrating Ivan Kupala Night, a traditional Slavic holiday not far from Kiev on July 6, 2013. During the celebration, originating in pagan times, people plait wreaths, jump over fires, and swim naked. (Photo by Sergei Supinsky/AFP Photo)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)