Onega River Onega River The Onega (; ) is a river in Kargopolsky, Plesetsky, and Onezhsky Districts of Arkhangelsk Oblast in Russia. The Onega connects Lake Lacha with the Onega Bay in the White Sea southwest of Arkhangelsk, flowing in the northern direction. The discharge at the source is and at the mouth is . The river is long, and the area of its basin . Its main tributaries are the Voloshka (right), the Kena (left), the Mosha (right), the Kodina (right), and the Kozha (left). The major tributary of the Lake Lacha is the Svid. The name of the river is
Onega River Monastery on an island in the Lake Kozheozero. Some of the finest monuments of the northern wooden architecture are located in the basin of the Onega, including ensembles of Lyadiny, Saunino Pogost, Krasnaya Lyaga, and Bolzhaya Shalga. These monuments also suffer from the lack of protection and their number steadily diminishes. In fact, the majority of them have been lost. The river splits into the Big Onega and Little Onega Rivers from its estuary, but then these branches join again, forming a big flat island. It freezes up in late October - early December and stays under the ice until