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 brilliant sunset makes for a fun silhouette picture by jumping between sand bars at Shi Shi Beach on the Olympic Peninsula Friday July 17, 2015. (Photo by Bettina Hansen/The Seattle Times)

Russian policemen detain participants of an unauthorized “Russian March 2020: For freedom and justice! We go out to say that Russian lives matter” organised by Russian nationalists on the National Unity Day in Moscow, Russia, 04 November 2020. Russian nationalists demand freedom for political prisoners in prisons and a fair investigation into the deaths of political prisoners, including representatives of radical movements who were killed during detention or found dead in places of detention. (Photo by Sergei Ilnitsky/EPA/EFE)

A restaurant worker wearing a mask cleans the windows as the restaurant reopens amid the COVID-19 pandemic in Sao Paulo, Brazil, Monday, July 6, 2020. Bars, restaurants and beauty salons were allowed to re-open Monday after over three months of quarantine, and are required to observe preventative measures and reduced operating hours only during the day. (Photo by Andre Penner/AP Photo)

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)

Russian Communist party activists and supporters carry portraits of Soviet founder Vladimir Lenin (R) and Soviet dictator Josef Stalin (L) as they attend a flowers-laying ceremony at the Lenin's Mausoleum on Red Square in downtown Moscow on November 7, 2021, marking the 104th anniversary of the Bolshevik Revolution also known as the October Revolution. (Photo by Dimitar Dilkoff/AFP Photo)

Kamaz' Russia driver Andrey Karginov, co-driver Andrey Mokeev and Igor Lenonov compete during the Stage 6 of the Dakar 2020 between Ha'il and Riyadh, Saudi Arabia, on January 10, 2020. (Photo by Franck Fife/AFP Photo)

Models prepare backstage before a creation from the Saint Joy by Bian Huizhong during the China Fashion Week in Beijing on March 30, 2023. (Photo by Wang Zhao/AFP Photo)