American Paralympic snowboarder Amy Purdy dances with a robot during the opening ceremony of the Rio 2016 Paralympic Games at the Maracana stadium in Rio de Janeiro on September 7, 2016. (Photo by Yasuyoshi Chiba/AFP Photo)

On the festival of Krishna Janmashtami, a girl costumed as Lord Krishna poses for a photo in Dhaka, Bangladesh on August 19, 2022. (Photo by Nayem Shaan/ZUMA Press Wire/Rex Features/Shutterstock)

A Vietnamese woman collects dried incense sticks at a courtyard in Quang Phu Cau village on the outskirts of Hanoi on January 9, 2020 ahead of the upcoming Lunar New Year celebrations, referred to in Vietnam as Tet. (Photo by Manan Vatsyayana/AFP Photo)

Eddy the badger is pictured as Nicanor goes to leave water and fruits for the animals affected by the fires, in San Buenaventura, Bolivia on November 26, 2023. (Photo by Claudia Morales/Reuters)

Maja, a 40-year-old elephant, extends her trunk into a bakery as a customer buys a newspaper while Maja took a stroll through the neighborhood with her minders from a nearby circus on July 1, 2016 in Berlin, Germany. (Photo by Sean Gallup/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)

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.