Lake Kenozero Lake Kenozero Lake Kenozero () is a freshwater lake, located in the south-west of Plesetsky District of Arkhangelsk Oblast in Russia. It is one of the biggest lakes in Arkhangelsk Oblast and the biggest one in Plesetsky District. The area of the lake is , and the area of its basin is . Lake Kenozero is the source of the Kena River, a tributary of the Onega River. The lake thus belongs to the Onega basin and the White Sea basin. The lake is located close to the border of Arkhangelsk Oblast and Republic of Karelia. It belongs to Kenozersky
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.