A round circle of smoke coming from the mouth of the Etna volcano is seen in the sky during an eruption on the southern Italian island of Sicily April 11, 2013. Mount Etna is Europe's tallest and most active volcano. (Photo by Antonio Parrinello/Reuters)

A visitor views the work of artists Gonzalo Duran and Cheri Pann at their Mosaic Tile House in Venice, California U.S., August 26, 2016. With an array of thrift store china, humorous souvenirs and handmade tile adorning its walls and floors, the Mosaic Tile House in Venice stands as a monument to two decades of artistic collaboration between Cheri Pann and husband Gonzalo Duran. (Photo by Mario Anzuoni/Reuters)

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.

In this photo taken late Thursday, May 7, 2015, a prison guard, left, and seated inmates cast shadows on a wall while waiting for the beginning of a rock concert by Romanian band Pro Musica, inside the Popa Sapca jail in Timisoara, western Romania. (Photo by Adi Piclisan/AP Photo)

Participants compete in a wife-carrying championship in Tapiobicske, Hungary, August 7, 2021. Some 40 Hungarian husbands, with their wives on their backs, clambered over rough terrain on Saturday in the nation's second wife-carrying contest. (Photo by Marton Monus/Reuters)

A young macaque perches on a pole, observing nearby tourists while eating some seeds in Jigokudani Yaen-koen wild macaque monkey park on February 16, 2015 in Yamanouchi, Nagano, Japan. (Photo by Manuel Romaris/Getty Images)

Young Legong dancer portrait, Ubud, Bali on October 25, 2023. While the childrens' parents are out working, in pursuits including farming, fishing and clothes making, their offspring spend the long sunny days making their own fun, and as these pictures show not a minute is wasted. (Photo by David Lazar/Animal News Agency)

Mamoni Mandal, member of the Rapid Action Force (RAF), attends a training session at a police training school in Kolkata April 15, 2007. (Photo by Parth Sanyal/Reuters)