When Japan introduced the Ritsuryo system (a system of centralized government based on the ritsuryo code) used in Sui and Tang in China, Japan built its capital and castle under a strong influence of the designs of the capitals and castles in Sui and Tang.
日本で隋・唐の律令制が導入されると、隋・唐の都城設計の強い影響を受け、都城を建設した。