A man is silhouetted as he stands on a walkway in the sky lobby at the Chancellery, the seat of German Chancellor Angela Merkel (not pictured) in Berlin, May 7, 2014. (Photo by Thomas Peter/Reuters)

Coca-cola mini kiosks by ogilvy & mather Berlin promote tiny coke cans. To promote the launch of its tiny coke cans, coca-cola and advertising agency ogilvy & mather berlin deployed and installed a series of miniature kiosks throughout five different major cities in Germany.

A demonstrator wearing a mask is seen during a protest against the government's restrictions amid the coronavirus disease (COVID-19) outbreak, in Berlin, Germany, August 1, 2020. (Photo by Christian Mang/Reuters)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

Motorcycle fans dressed as Santa Claus ride near Charlottenburg Palace (Schloss Charlottenburg)during the 25th annual “Santa Claus On Road” Berlin Bike Tour, to deliver gifts to the needy on December 10, 2022 in Berlin, Germany. Some 200 riders with vehicles decorated with lights and mini-Christmas trees took part in the annual event on its 25 year. Anyone may ride along, whether on motorcycle, trike or quad, as long as the vehicle is decorated accordingly. (Photo by Omer Messinger/Getty Images)

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 frozen public bench is seen next to a lake side due to the heavy wind conditions in Geneva February 8, 2015. (Photo by Pierre Albouy/Reuters)

The Verzasca is a Swiss 30-km long mountain river originating at Pizzo Barone and flowing into Lake Maggiore. It is known for its clear turquoise water and vibrant colored rocks, as well as its treacherous currents. The Verzasca Dam is a few kilometers upriver from this lake.