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Selenga River

river, Asia
Also known as: Selenge Mörön

Selenga River, river in Mongolia and east-central Russia. It is formed by the confluence of the Ider and Delger rivers. It is Mongolia’s principal river and is the most substantial source of water for Lake Baikal.

The Delger rises in the Sangilen Mountains on the border between Mongolia and the Russian republic of Tyva (Tuva), and the headwaters of the Ider lie in the Hangayn Mountains in Mongolia to the south. From their confluence the Selenga flows northeast to receive the Orhon River at SĂŒhbaatar. It continues north into Russia and bends eastward to Ulan-Ude, capital of Buryatia. From there the river flows north to Tataurovo, where it swings westward and then flows through a delta into Lake Baikal. From SĂŒhbaatar to its mouth the Selenga flows down a gentle slope, giving Mongolia access to the plains of Siberia (Asiatic Russia). The Trans-Siberian Railroad follows the river’s valley upstream to Ulan-Ude, where a branch continues to SĂŒhbaatar, and then up the Orhon to Ulaanbaatar, the capital of Mongolia.

The Selenga is 920 miles (1,480 km) long and is navigable from its mouth to beyond SĂŒhbaatar in May–October, when it is ice-free. The river basin has a subarctic climate, with severe winters and warm summers. The river freezes from November to April, and snowmelt increases the river’s flow during the spring and early summer. Its 173,000-square-mile (448,000-square-km) basin includes the Mongolian tributaries the Orhon, Hanuy, and Egiyn and the Russian Chikoy, Khilok, Uda, Dzhida, and Temnik rivers.

Tower Bridge over the Thames River in London, England. Opened in 1894. Remains an Important Traffic Route with 40,000 Crossings Every Day.
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This article was most recently revised and updated by Amy Tikkanen.
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