Playboy Bunnies pose for a selfie at the premiere of “The Transporter Refueled” at Playboy Mansion in Los Angeles, California August 25, 2015. The movie opens in the U.S. on September 4. (Photo by Mario Anzuoni/Reuters)

A Maasai boy bites a bull's heart during an initiation into an age group ceremony near the town of Bisil, Kajiado county, Kenya, August 23, 2018. Thousands of Kenyan boys had a blessing of milk and beer sprayed on them as part of a rare Maasai ethnic community initiation ceremony to mark their passing into early manhood. (Photo by Baz Ratner/Reuters)

A woman looks at La Paz city from the Jacha Qhatu cable car station in El Alto, July 23, 2015. Bolivia already has the largest urban cable car system in the world. Now the booming country is tripling the size of the network and will soon have nine lines whizzing above the administrative capital of La Paz. (Photo by David Mercado/Reuters)

Russian honour guards wearing protective masks attend the opening ceremony of the 6th International Military Technical Forum “Army 2020” and Army Games in the military Patriot Park outside Moscow on August 23, 2020. (Photo by Kirill Kudryavtsev/AFP Photo)

A weeping South Vietnamese mother and her three children are shown on the deck of this amphibious command ship being plucked out of Saigon by U.S. Marine helicopters in Vietnam, April 29, 1975. (Photo by AP Photo)

Brazilian model Izabel Goulart for the screening of the film “Sink Or Swim (Le Grand Bain)” at the 71st Cannes Film Festival, France on May 13, 2018. (Photo by Stephane Mahe/Reuters)

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)

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.