| From the Asuka to the Nara periods, invasions from the Tang Dynasty China and the Korean Silla Kingdom led to the construction of ancient mountain castles (Korean style mountain castles) throughout Western Japan. |
その後、飛鳥時代から奈良時代にかけて、唐や新羅の侵攻に備えて西日本各地に古代山城（朝鮮式山城）が築かれた。 |