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.

Iranian worshippers chant slogans during a protest after their Friday prayer, as part of widespread anger across the Muslim world about a film ridiculing Islam's Prophet Muhammad on September 14, 2012. (Photo by Vahid Salemi/Associated Press)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

Actors dressed as Father Frost perform in the main building of the Domodedovo airport named after Mikhail Lomonosov in Moscow, Russia, 27 December 2021. Russians are preparing to celebrate New Year's Eve on 31 December and Christmas which is observed on 07 January, according to the Russian Orthodox Julian calendar, 13 days after Christmas on 25 December on the Gregorian calendar. (Photo by Sergei Ilnitsky/EPA/EFE)

Traditional dancers with their masks look on before their performance during “Nawa Durga Nach” Hindu dance festival in Bhaktapur on the outskirts of Kathmandu on March 28, 2024. (Photo by Prakash Mathema/AFP Photo)

People take pictures with public art instalation titled “GIANTS: Rising Up” by the French artist JR, at Harbour City, Hong Kong, China on March 16, 2023. (Photo by Lam Yik/Reuters)

“Are you here for the Winery Tour?” This is a Western Grey Kangaroo caught lounging in the wineries of the Adelaide Hills in South Australia. This past Autumn has been a spectacular time for wildlife viewing and I got lucky to spot this guy while mountain biking in the hills. Such a funny stance it just begs the question... Have you been drinking? ...and or... Are you here for the Winery Tour? Such a spontaneous moment I figured it would be perfect for an entry. I hope you like it! Cheers. Photo location: Adelaide Hills, South Australia, Australia. (Photo and caption by Greg Snell/National Geographic Photo Contest)

Truffle hunter Carlo Marenda pets his dog Buc as they search for white truffles through the Langhe Countryside in Roddi, near Alba, north-western Italy, on November 8, 2020. Despite new measures to stop the spread of the Covid-19, truffles hunters are allowed to search in the countryside in Italy. (Photo by Marco Bertorello/AFP Photo)