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.

An invited guest enjoys a private listening experience of a test unit of the Sennheiser HE 1 sound system, which is expected to retail for about S$77370 ($55000), in a hotel suite during the CanJam headphone and personal audio expo in Singapore February 21, 2016. (Photo by Edgar Su/Reuters)

Kat Von D attends her first solo art show “New American Beauty” at Sephora Antara store on March 1, 2012 in Mexico City, Mexico. (Photo by Victor Chavez/Getty Images For Sephora)

View of a Spitfire from the cockpit of an He111,somewhere over Southern England 1941 – 2014. (Photo by Adam Surrey)

A British Spitfire and an American P-51 Mustang from Ultimate Warbird Flights take to the Northamptonshire on August 14, 2020 skies to mark the 75th anniversary of VJ Day. (Photo by Richard Pohle/The Times)

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)