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.

A couple wearing protective masks take a picture of a rose on Valentine's Day in Kuala Lumpur, Malaysia on February 14, 2022. (Photo by Hasnoor Hussain/Reuters)

This photo taken on October 30, 2022 shows people in costumes walking on the street during a celebration ahead of Halloween in Guangzhou in China's southern Guangdong province. (Photo by AFP Photo/China Stringer Network)

Actors Ryan Reynolds, Blake Lively, fashion model Gigi Hadid and Hugh Jackman attend the premiere of “Deadpool and Wolverine” in New York City, New York, U.S., July 22, 2024. (Photo by Caitlin Ochs/Reuters)

Some 1,250 students from the Assumption College flip their cards to form an image of Thailand's late King Bhumibol Adulyadej, in his honour, in Bangkok, Thailand, October 28, 2016. (Photo by Athit Perawongmetha/Reuters)

Pedestrians look at the wreckage of a vehicle lodged in a storm drain on a street in Abidjan on June 19, 2018, in which a man was reportedly found dead after floodwaters receded following an overnight downpour in the city. Fifteen people have died in Abidjan, Ivory Coast' s economic capital, during flooding caused by torrential rain overnight, Interior Minister Sidiki Diakite said. Rain poured down overnight on June 19, causing flash floods up to 2.5 metres (more than eight feet) deep, he said. (Photo by Sia Kambou/AFP Photo)

Tribal artists and supporters from the southern Indian state of Karnataka dance outside the residence of Congress Party President Sonia Gandhi during her birthday celebrations in New Delhi, India, Wednesday, December 9, 2015. The Italian-born Gandhi is the widow of former Prime Minister Rajiv Gandhi and has led the Congress party since 1998. (Photo by Altaf Qadri/AP Photo)

Natalia Grossman of the USA competes during the women's finals of the IFSC Climbing World Cup Meiringen on April 09, 2022 in Meiringen, Switzerland. (Photo by Marco Kost/Getty Images)