Dvina Bay streams. There are many small islands in the Dvina Bay as well, the biggest being Mudyug Island. A national park, Onezhskoye Pomorye National Park, was open on the Onega Peninsula on 26 February 2013. The Dvina Bay is limited by the Onega Peninsula from the west. At the eastern side, the shore steeply rises to a plateau (White Sea - Kuloy Plateau) which drains east into the Soyana, a major tributary of the Kuloy. The Onega Bay shore is often referred to as "Letny Bereg" (Summer Coast), and the eastern shore of the bay is "Zimny Bereg" (Winter Coast). The
Arkhangelsk evidence of a stronger case of Russian colonization than previously thought. In the 12th century, the Novgorodians established the Archangel Michael Monastery (named after Michael the Archangel) in the estuary of the Northern Dvina River. The main trade center of the area at that time was Kholmogory, located southeast of Arkhangelsk, up the Dvina River, about downstream from where the Pinega River flows into the Dvina. Written sources indicate that Kholmogory existed early in the 12th century, but there is no archeological material to illuminate the early history of the town. It is not known whether the origin of this