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.

Tandem hair drying is possible with a new two-hood attachment for any electric hair dryer manufactured by Postcraft Co of Tucson, Ariz., shown in Chicago, January 27, 1965. A Y adapter permits two hoses to be attached to the dryer. (Photo by Edward Kitch/AP Photo)

Dancer Elizabeth Suarez, 29, gets ready to perform at the backstage of a cinema where the “Cuerda Viva” (Live Strings) alternative music festival is taking place, in Havana, February 26, 2016. (Photo by Alexandre Meneghini/Reuters)

A man applies coats of glass powder to kite strings ahead of the Hindu festival “Uttarayan” in Ahmedabad on December 21, 2023. (Photo by Sam Panthaky/AFP Photo)

A string art picture made by artist Ani Abakumova in a workshop in the village of Romashkovo in Moscow Region, Russia on August 2, 2019. Ani Abakumova and her husband Andrei Abakumov create string art replicas of famous paintings. Andrei makes computer calculations that show patterns for future images, then Ani winds coloured strings around nails hammered around a plywood board. (Photo by Anton Novoderezhkin/TASS)

A girl plays kayagum, stringed Korean harp, at the Tongmun kindergarten No.1 in Taedonggang District of Pyongyang, North Korea Tuesday, May 16, 2023. (Photo by Cha Song Ho/AP Photo)

Soldiers try to attach the balloon to their car, June 1944. (Photo by Jared Enos/Mediadrumworld.com)

Female members of the Chinese People's Liberation Army (PLA) honour guard stand behind a string to ensure that they are in a straight line before a welcoming ceremony for Russian President Vladimir Putin outside the Great Hall of the People in Beijing, China, June 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)