Construction and Characteristics of Capital’s Castle in the Gangdo Period of Goryeo Dynasty

Capital’s Castle in the Gangdo(江都) was composed of Royal Palace(宮城), Middle Castle(中城; Inner Castle 內城), and Outside Castle(外城). It accepts that Gaegyeong(開京) was composed of Royal Palace, Hwangseong(皇城), and Naseong(羅城). Capital’s Castle in the Gangdo was structured Royal Palace and Outside Castle at first. Because Goryeo Dynasty made war against the Mongol Empire, so that was urgently transferred to Ganghwa Island. But the war was more drawn out, and was structured Middle Castle by Choi Hang(崔沆) at the 37th year of King Gojong(高宗) reign. At last, there finished three castle system. We can know Royal Palace gate name, the others can’t. But it perhaps was built Royal Palace in construction work course of Capital’s Castle. I assert that Middle Castle is equal to Inner Castle in the Gangdo. Because it was records about building of Middle Castle, but it was not records that the building was destroyed by Mongol Empire’ exaction at the 46th year of King Gojong reign. Capital’s Castle in the Gangdo was symbol building of opposition to Mongol empire. Therefore it is impossible that wasn't records about Middle Castle destruction. It prove that Inner Castle, first destruction building is exactly Middle Castle. Royal palace differ with Inner Castle. The Gangdo was not only island but also unimportant spot military, so must construct a line of defense at Gapgot(甲串), the east coast. But the line of defense is not Outside Castle. Outside Castle protected Royal Palace, government office, etc., also was symbol of Capital’s Castle in the Gangdo. As a result, Outside Castle was castle walls constructed around Capital’s Castle. Subject of research in the future must reflect excavation of Capital’s Castle.