Oka

Oka, river, c.600 mi (970 km) long, rising in the Sayan Mts., Buryat Republic, S central Siberian Russia. It flows N through Irkutsk oblast to join the Angara River below Bratsk. The lower Oka valley is flooded by waters impounded behind Bratsk Dam.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

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