The Upper Angara River is a river in Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

 to the north of Lake Baikal

Lake Baikal

Lake Baikal is the world's oldest at 30 million years old and deepest lake with an average depth of 744.4 metres.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...

. It is 320 km long and rises north-east of Lake Baikal

Lake Baikal

Lake Baikal is the world's oldest at 30 million years old and deepest lake with an average depth of 744.4 metres.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...

, flowing south-west through the Buryat Republic and eventually into the lake. It is partly navigable. The Baikal Amur Mainline runs along the north side of the river northeast up its valley, crossing between Anamakit and Novy Uoyan

Novy Uoyan

Novy Uoyan is an urban locality in Severo-Baykalsky District of the Republic of Buryatia, Russia, located in the basin of the Upper Angara River, from Ulan-Ude and from Nizhneangarsk...

and crossing the river a second time upstream before heading into the mountains.