As the Ritsuryo System (a system of centralized government based on the Ritsuryo Code) declined during the Heian period, the city gradually expanded beyond its original area to become centered around the Kamo-gawa River and the Kyoto Imperial Palace of the Daidairi (Greater Imperial Palace), and developed economically.
平安時代の律令制の形骸化にともなって次第に本来の領域にとらわれない、鴨川と大内裏・京都御所を中心とする都市になり、経済的に発展していった。