Onega River Kozhozero, as well as Kenozersky National Park. The whole valley of the Onega is populated, with the exception of the stretch between Severoonezhsk and Yarnema, in Plesetsky District. There are two towns located on the Onega River, Kargopol close to its source and Onega in its mouth. There are also two urban-type settlements, located opposite to each other in the middle course of the river, Oksovsky (right bank) and Severoonezhsk (left bank). of the river's lower course, between the village of Gorodok and the selo of Porog, is listed in the State Water Register of Russia as navigable. The rest
Lake Onega the last Ice Age, about 12,000 years ago: In the Paleozoic Era (400–300 million years ago) the entire territory of the modern basin of the lake was covered with a shelf sea lying near the ancient, near-equatoric Baltic continent. Sediments at that time – sandstone, sand, clay and limestone – form a layer covering the Baltic Shield which consists of granite, gneiss and greenstone. The retreat of the Ice Age glaciers formed the Littorina Sea. Its level was first higher than at present, but it gradually lowered, thereby decreasing the sea area and forming several lakes in the Baltic region.