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.

La Traviata chandelier is positioned on stage at Mrs Macquarie's Point on March 16, 2012 in Sydney, Australia. Covered with 10,000 Swarovski crystals, the 9 metre high chandelier will be hung above the performing stage of the La Traviata Opera. (Photo by Brendon Thorne/Getty Images)

The Flying Bull's P-38 Lockheed Lightning N25Y / 13 – Red Bull – Flying Legends Airshow 2012 Duxford (Photo by Rob Lovesey)

Bison along the Bitterroot Valley's Eastside Highway north of Stevensville, Montana, are covered in snow following a blizzard on November 23, 2010. (Photo by Perry Backus/The Missoulian)

Women carry a portable shrine, a Mikoshi, through a street in Tokyo's Asakusa district during the Sanja festival, Japan, May 15, 2016. (Photo by Thomas Peter/Reuters)

A juvenile specimen of the recently-discovered Australian Peacock spider, Maratus Albus, sits on the nib of a pencil in this undated picture taken in Western Australia's Nuytsland Nature Reserve. (Photo by Jurgen Otto/Reuters)

A hostess sits at a restaurant with paintings depicting Thailand's King Bhumibol Adulyadej hanging on a wall in Bangkok, Thailand, June 6, 2016. (Photo by Athit Perawongmetha/Reuters)