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 girl holds her hedgehog to be blessed by a priest at the Cathedral San Bernardino de Siena during the ceremony commemorating the Feast of San Antonio Abad, the patron saint of domestic animals, in Xochimilco on the outskirts of Mexico City, Mexico on January 17, 2024. (Photo by Raquel Cunha/Reuters)

The company selling wedding dresses with designs made of local and wild grass, exhibited its new collection with local and foreign models consisting of Mesopotamian motifs by organizing a fashion show at Dara Ancient City in Mardin, Turkiye on February 26, 2025. (Photo by Halil Ibrahim Sincar/Anadolu via Getty Images)

A Cambodian girl goes through the garbage dump looking for things to recycle in order to survive July 26, 2003 in Phnom Penh, Cambodia. Rampant corruption in this impoverished country has lead to extreme poverty with many Cambodians living below the poverty line. (Photo by Paula Bronstein/Getty Images)

Ohio State drum major performs during the NCAA football game between the Ohio State Buckeyes and Notre Dame Fighting Irish at Ohio Stadium in Columbus on September 3, 2022. (Photo by Adam Cairns/USA TODAY Sports)

Photographer holding digital camera during photoshoot of fashion model. (Photo by grinvalds/Getty Images)

Groups of dressed-up pals took to the streets of Leeds, United Kingdom for famous Otley run on Saturday, March 2, 2024. (Photo by NB Press LTD)

A tourist has her photo taken wearing a Santa hat on Christmas Day on Bondi Beach in Sydney, Australia on December 25, 2018. (Photo by Peter Parks/AFP Photo)