A Polisario fighter sits on a rock at a forward base on the outskirts of Tifariti, Western Sahara, September 9, 2016. At a rocky outpost in Western Sahara, a new generation of soldiers who have never known war are mobilising as tensions resurface in one of Africa's oldest disputes after a quarter century of uneasy peace. (Photo by Zohra Bensemra/Reuters)

French performer Odile De Mainville applies a makeup backstage before the Parisian transvestite cabaret show at “Madame Arthur” in Paris, on September 29, 2023. Open since 1946, Madame Arthur is the oldest transformist cabaret in Paris. Threatened with extinction the cabaret is undergoing a renaissance, attracting younger customers by returning to the fundamentals of the lie: baroque and queer performers who play with genres and conventions, and sing French hits live. (Photo by Joel Saget/AFP Photo)

French performer Maud'Amour applies a makeup backstage before the Parisian transvestite cabaret show at “Madame Arthur” in Paris, on September 29, 2023. Open since 1946, Madame Arthur is the oldest transformist cabaret in Paris. Threatened with extinction the cabaret is undergoing a renaissance, attracting younger customers by returning to the fundamentals of the lie: baroque and queer performers who play with genres and conventions, and sing French hits live. (Photo by Joel Saget/AFP Photo)

Lioness and hyena posture to one another, in Masai Mara, Kenya, August 2015. A photographer captured one of the oldest rivalries in the animal kingdom as a pair of lions went head to head with a pack of hungry hyenas. (Photo by Ingo Gerlach/Barcroft Images)

Students dance in the hallway during a break at Moscow State Academy of Choreography in Moscow, Russia 03 March 2016. Moscow State Academy of Choreography is the oldest institution in Moscow which teaches Ballet arts not only Russian citizens, but also representatives from more than 20 countries. (Photo by Yuri Kochetkov/EPA)

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.

Female Chimpanzee “Fifi” eats carrots as she sits in her enclosure at Taronga Zoo on her 60th birthday May 21, 2007 in Sydney, Australia. Fifi is the oldest of the Zoo's chimp population, which consists of 19 individuals. (Photo by Ian Waldie/Getty Images)