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.

A man photographs the main engines of the space shuttle orbiter Discovery on display at the Udvar-Hazy Smithsonian National Air and Space Annex Museum in Chantilly, Virginia August 28, 2015. Shuttle Discovery had 27 years of service and flew 39 times before being retired in 2011. (Photo by Gary Cameron/Reuters)

Tourists kissing front of Malaysia's landmark Petronas Twin Towers with lights on before turned off to mark Earth Hour 2016 in Kuala Lumpur, Malaysia, 19 March 2016. Earth Hour takes place worldwide at 8.30 p.m. local time and is a global call to turn off lights for 60 minutes to raise awareness of the danger of global climatic change (Photo by Fazry Ismail/EPA)

Jeff and Kelly Lyons clear the first obstacle while competing in the North American Wife Carrying Championship at Sunday River ski resort in Newry, Maine October 11, 2014. (Photo by Brian Snyder/Reuters)

Cute sеxy caucasian brunette young woman dressed as Mrs. Santa Claus, smiling with joy, biting a candy cane with eyes closed, Christmas or New Years Eve 2022 concept. (Photo by Cryptographer/Rex Features/Shutterstock)

France's Alize Cornet falls down during her women's singles tennis match against Kazakhstan's Elena Rybakina on the fourth day of the 2023 Wimbledon Championships at The All England Tennis Club in Wimbledon, southwest London, on July 6, 2023. (Photo by Glyn Kirk/AFP Photo)

A U.S. soccer fan pretends that Uruguay's soccer striker Luis Suarez is biting him as he takes a selfie next to an Adidas advertisement featuring Suarez near Copacabana beach in Rio de Janeiro, Brazil, Thursday, June 26, 2014. FIFA banned Suarez from all football activities for four months on Thursday for biting an opponent at the World Cup, a punishment that rules him out of the rest of the tournament. (Photo by Matt Dunham/AP Photo)

Men stroll past roadside vendors as a painted truck makes its way through the busy street in Kabul, Afghanistan, November, 1961. (Photo by Henry S. Bradsher/AP Photo via The Atlantic)