Kargopolsky District subordinated to the central administration of Northern Krai. In 1936, the krai was transformed into Northern Oblast. In 1937, Northern Oblast itself was split into Arkhangelsk Oblast and Vologda Oblast. Kargopolsky District remained in Arkhangelsk Oblast ever since. The district is almost exclusively located in the basin of the Onega River, which is the biggest river in the district, and belongs to the basin of the White Sea. The source of the Onega is Lake Lacha, which is the biggest lake in the district. The northeastern shore of Lake Vozhe, also in the basin of the Onega, belongs to Kargopolsky
Arkhangelsk Oblast the 1970s and is expected to become part of the Belkomur project — a railway line connecting Arkhangelsk via the Komi Republic with the Perm Krai and the Ural mountains. Almost the entire rail network belongs to the Northern Railway, which west of Onega connects to the Oktyabrskaya Railway. There is also a railway line from Severoonezhsk west to Yangory (an extension of the line from Puksa to Navolok), which belongs to the Department of Corrections. A big number of narrow gauge railways have been built in the 1950s and 1960s to facilitate the transport of timber, but since then