Donggosanseong Fortress

Donggosanseong is a mountain fortress built during the Unified Silla period. Its name was given during the reign of King Sunjo of the Joseon Dynasty when the fortress across from it was called [Namgosanseong]. The fortress has a circumference of 1,712m, measuring 314m east-west and 256m north-south, making it a relatively large mountain fortress. The walls were constructed using the valley-surrounding (pogok-sik) method. It has been presumed since ancient times to be the palace fortress of Wansanju, which was the capital of King Gyeon Hwon, who founded Later Baekje. During an excavation in 1990, a building site measuring 22 kan in front and 3 kan on the sides, totaling 66 kan in area, was discovered. This is the largest single building site excavated in Korea, supporting the claim that this was the palace of King Gyeon Hwon.