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.

Bella Hadid, Vittoria Ceretti and Gigi Hadid are seen backstage ahead of the Alberta Ferretti show during Milan Fashion Week Spring/Summer 2018 on September 20, 2017 in Milan, Italy. (Photo by WWD/Rex Features/Shutterstock)

A child poses on the runway during a party hosted by Chasing Fireflies to introduce Gwen Stefani's Harajuku Lovers children's collection at Duff's Cakemix on September 24, 2015 in West Hollywood, California. (Photo by Frazer Harrison/Getty Images for Chasing Fireflies)

Russian actor Dmitriy Grachev (C) parodies Vladimir Putin as he presents a creation by Russian designer Ilya Shiyan during the Moscow Fashion Week Autumn/Winter 2019-2020, in Moscow, Russia, 24 March 2019. (Photo by Maxim Shipenkov/EPA/EFE)

The Monse collection is prepared backstage during Fashion Week, Friday, February 7, 2020, in New York. (Photo by John Minchillo/AP Photo)

Dancers perform during La Paz Fashion Week in La Paz, Bolivia, February 7, 2019. (Photo by David Mercado/Reuters)

American rapper and songwriter Lil' Kim performs as she presents a creation from The Blonds Autumn/Winter 2019 collection during New York Fashion Week in New York, U.S. on February 12, 2019. (Photo by Andrew Kelly/Reuters)

A masked man in military fatigues brings a blindfolded Irma Krat, arrested and held by pro-Russian protestors before her meeting with journalists near of occupied police station in Slaviansk, Ukraine, 21 April 2014. Pro-Russian activists are demanding broader autonomy from Kiev and closer ties to Russia. Pro-Russian activists continued occupying government, police and other administrative buildings in eastern Ukrainian cities, in defiance of an ultimatum by the Ukrainian government to lay down their weapons. Russia, the United States, the European Union and Ukraine on 17 April had agreed on steps to de-escalate the crisis in Ukraine during talks in Geneva, Switzerland. (Photo by Roman Pilipey/EPA)