Lake Baikal is the world's oldest lake, at 25 million years (possibly older), and deepest, averaging 744.4 metres (2,442 ft).

Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the world, containing roughly 20% of the world's unfrozen surface fresh water.

Participants compete in a wife-carrying championship in Tapiobicske, Hungary, August 7, 2021. Some 40 Hungarian husbands, with their wives on their backs, clambered over rough terrain on Saturday in the nation's second wife-carrying contest. (Photo by Marton Monus/Reuters)

A young macaque perches on a pole, observing nearby tourists while eating some seeds in Jigokudani Yaen-koen wild macaque monkey park on February 16, 2015 in Yamanouchi, Nagano, Japan. (Photo by Manuel Romaris/Getty Images)

Young Legong dancer portrait, Ubud, Bali on October 25, 2023. While the childrens' parents are out working, in pursuits including farming, fishing and clothes making, their offspring spend the long sunny days making their own fun, and as these pictures show not a minute is wasted. (Photo by David Lazar/Animal News Agency)

A fan runs on the field during the fourth quarter of Super Bowl LV between the Tampa Bay Buccaneers and the Kansas City Chiefs at Raymond James Stadium on February 07, 2021 in Tampa, Florida. (Photo by Mike Ehrmann/Getty Images)

Children play marbles on the dirt in Garut, West Java, Indonesia on October 17, 2025. This traditional game, which was popular in the 1980s, is now rarely played by children due to the increasing popularity of modern games with advanced technology. According to a survey by the Indonesian Child Protection Commission (KPAI), more than 71.3% of school-age children own gadgets and play them for a considerable amount of time each day, and as many as 79% of child respondents are allowed to play gadgets for purposes other than learning. (Photo by Algi Febri Sugita/ZUMA Press Wire/Rex Features/Shutterstock)

People hold umbrellas as they walk past a flooded street in Taiyuan, Shanxi Province, China, July 19, 2016. (Photo by Reuters/China Daily)

Children residents take a selfie as they wait for the police to dance, an unconventional approach to connect the police with the community in rough neighbourhoods, as part of the “Tirando Barrio” (Marking territory) programme in Saltillo, Northern Mexico September 9, 2016. T-Shirt reads “Street Dancers”. (Photo by Daniel Becerril/Reuters)