Arkhangelsk Oblast the south-west of the Oblast drains into the Kema River which belongs to the basin of the Caspian Sea. The area in the Onega River basin containing the biggest lakes in the oblast, such as Lake Lacha, Lake Kenozero, Lake Undozero, and Lake Kozhozero. The tundra of the Nenets Autonomous Okrug also contains a number of bigger lakes. The river basin of the Pinega is characteristic of the karst, with a number of caves in the region. The White Sea coast within the Oblast is split into the Onega Bay (where the Onega is the major tributary), the Dvina Bay
Arkhangelsk Oblast distinct population of polar bears associated with the Barents Sea area. Almost all of the area of the Oblast belongs to the basin of the Arctic Ocean, with the major rivers being (west to east) Onega River, Northern Dvina River (with the major tributaries the Vychegda, the Vaga, and the Pinega), Kuloy River, Mezen River, and Pechora River (Shapkina River being a major tributary). A minor area in the west of the Oblast, most notably the basin of the Ileksa River, drains into the Lake Onega and eventually to the Baltic Sea. A very minor area in Kargopolsky District in