It is a river in Mongolia and Russia, 1024 km long, pow. Basin 447 thousand. km2; arises from a combination of government. Ider-gol and Delger-Moron, is considered a delta (area about 700 km2) of Lake Baikal; depth. tributaries Orchon, Czikoj, Chiłok, Will (pr.), Egijn-gol (l) for 5 months a year frozen, navigable for most of the race (very important for the economy of Mongolia), the main town on the Selenga Ulan-Ude - the capital Buryatia.
