Lake Baikal, Siberia, Russia

In July 2008, Russia sent two small submersibles, Mir-1 and Mir-2, to descend 1,592 m (5,223 ft) to the bottom of Lake Baikal to conduct geological and biological tests on its unique ecosystem. Although originally reported as being successful, they did not set a world record for the deepest fresh water dive, reaching a depth of only 1,580 m (5,180 ft). That record is currently held by Anatoly Sagalevich, at 1,637 m (5,371 ft) (also in Lake Baikal aboard a Pisces submersible in 1990). Russian scientist and federal politician, Artur Chilingarov, also joined the 60 dives.
Russian exploration and conquest
Russian expansion into the Buryat area around Lake Baikal in 1628–1658 was part of the Russian conquest of Siberia. It was done first by following the Angara River upstream from Yeniseysk (founded 1619) and later by moving south from the Lena River. Russians first heard of the Buryats in 1609 at Tomsk. According to folktales related a century after the fact, in 1623, Demid Pyanda, who may have been the first Russian to reach the Lena, crossed from the upper Lena to the Angara and arrived at Yeniseysk. Vikhor Savin (1624) and Maksim Perfilyev (1626 and 1627–1628) explored Tungus country on the lower Angara. To the west, Krasnoyarsk on the upper Yenisei was founded in 1627. There were a number of ill-documented expeditions eastward from Krasnoyarsk. In 1628 Pyotr Beketov first encountered a group of Buryats and collected yasak from them at the future site of Bratsk. In 1629 Yakov Khripunov set off from Tomsk to find a rumored silver mine. His men soon began plundering both Russians and natives. They were joined by another band of rioters from Krasnoyarsk but left the Buryat country when they ran short of food. This made it difficult for other Russians to enter the area. In 1631 Maksim Perfilyev built an ostrog at Bratsk. The pacification was moderately successful, but in 1634 Bratsk was destroyed and its garrison killed. (The story goes that the Buryats did not know how to use firearms, so they decided to burn the muskets along with the dead Cossacks. The fire caused the guns to go off, killing a few people which made the Buryats think that the Russians were still fighting after they were dead.) In 1635 Bratsk was restored by a punitive expedition under Radukovskii. In 1638 it was besieged unsuccessfully.