A visitor holds an Israeli-made rifle during the 8th International Land and Naval Defense system exhibition, in New Delhi, India, on February 6, 2014. (Photo by Anindito Mukherjee/Reuters)

Balinese traditional dancers take selfie as they await the arrival of G20 leaders at Ngurah Rai International airport at Tuban, Badung regency on Indonesia resort island of Bali, on November 13, 2022. (Photo by Sonny Tumbelaka/AFP Photo)

Camelot, with rider Kris Anderson, wins an exhibition race billed as “The Cameltonian” at the Meadowlands Race Track in East Rutherford, New Jersey June 21, 2014. Run by Hedrick's Promotions in Nickerson, Kansas, this is the third year the race has been run at the track, in tandem with an ostrich race. (Photo by Ray Stubblebine/Reuters)

Indonesian residents look at the Mount Sinabung volcano as it spews volcanic ash near the Tiga Pancur village in Karo, North Sumatra on August 3, 2016. Volcanic eruptions in Indonesia in recent days have forced the closure of two airports and disrupted some flights to the holiday island of Bali, officials said August 3. Mount Sinabung, a volcano on the western island of Sumatra which has been rumbling for some time, also erupted violently on August 2, although its ash clouds did not disrupt any flights. (Photo by Y.T. Haryono/AFP Photo)

This photo taken on August 7, 2016 shows mahjong enthusiasts playing mahjong under water in a swimming pool at a diving club in the Chinese city of Chongqing. Only participants with proper diving certification were allowed to take part in the underwater competition. (Photo by AFP Photo/Stringer)

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.