Which river is the only outflow of Lake Baikal?

The Angara River is the only outflow of Lake Baikal.

Baikal receives water from roughly 330 rivers, including the Selenga, Barguzin, and Upper Angara. All of that drainage leaves through a single outlet: the Angara, which begins near the settlement of Listvyanka at the lake’s southwestern end. This unusual one-outlet system helps make Baikal a distinctive and exceptionally old freshwater basin.

The Angara flows generally north and west through Siberia, passing Irkutsk, Bratsk, and Ust-Ilimsk before joining the Yenisei River near Strelka. The Yenisei then continues north toward the Arctic Ocean. That relationship causes a common quiz mistake: the Yenisei is the larger river system that ultimately receives Baikal’s water, but it is not Baikal’s direct outflow.

Lake Baikal is also the world’s deepest lake, reaching about 1,642 metres, and holds approximately 22–23% of the world’s unfrozen surface freshwater. Its 25–30-million-year geological history and many endemic species make the Angara’s single outlet part of a much larger scientific story.