The facilities where the Kokushi administered the government affairs were called "Kokucho" under the Ritsuryo system (a system of centralized government based on the ritsuryo code), whose surroundings were squarely demarcated by a fence or other means.
律令制において、国司が政務を執った施設を国庁といい、国庁の周囲は塀などによって方形に区画されていた。