Velikiye Luki Oblast
On June 1, 1936 Seryozhinsky District with the administrative center located in the selo of Bologovo was established. The district was a part of Kalinin Oblast. On August 23, 1944 it was transferred to Velikiye Luki Oblast, and on October 2, 1957 it was transferred back to Kalinin Oblast. On January 12, 1960 Seryozhinsky District was abolished and split between Leninsky and Toropetsky Districts.