Плесецкий район
Between July 15, 1929 and January 1, 1963, Priozyorny District with the administrative center in the "selo" of Konyovo existed and was a part of Northern Krai, Northern Oblast, and then Arkhangelsk Oblast. In 1963, it was merged with Plesetsky District. In 1966, Mirny, at the time a work settlement, was transferred from Plesetsky District to the oblast administration.