Onega River traditionally explained as related to Finnish "Enojoki" - the main river, stream. In terms of both area of the basin and the average discharge, the Onega is the third river basin of the White Sea (behind the Northern Dvina and the Mezen. The river basin of the Onega is spread over the west of Arkhangelsk Oblast, north-west of Vologda Oblast, and also includes minor areas in the east of Republic of Karelia. The Onega basin includes some of the biggest lakes of Arkhangelsk and Vologda Oblasts, such as Lake Vozhe, Lake Lacha, Lake Lyokshmozero, Lake Kenozero, Lake Undozero, and Lake
Arkhangelsk Governorate Arkhangelsk Oblast (and later the Arkhangelsk Viceroyalty) was subdivided into seven uyezds (the administrative centers, which all had the town status, are given in parentheses), Mezen, Onega, and Pinega were incorporated as towns in 1780 just to become the uyezd towns. Kola was incorporated in 1784. In 1801, portions of the Povenetsky Uyezd were transferred to the Olonets Governorate, while the Kemsky Uyezd, with its center in Kem, was left to remain in the Arkhangelsk Governorate. In 1854, the town of Kola was destroyed during the Crimean War, and Kolsky Uyezd was merged into the Kemsky Uyezd. In 1883, the