Eupseong refers to a walled town housing government offices and commoner’s houses with a wall-fortress built around it. This fortress was built in the Goryeo Dynasty to ward off the Japanese pirates from the east and the Yeojin Tribes from the north. According to the records of Goryeosa (History of the Goryeo Dynasty) and Sinjeung dongguk yeoji seungnam (New Augmented Survey of the Geography of Korea), it was initially built with mud and dirt in 1011, the 2nd year of the reign of King Hyeonjong of the Goryeo Dynasty, but was later rebuilt with stones during the Joseon Dynasty. This oval fortress has circumference of 1440m and 3 main gates with a Barbican built to protect the gates of the main fortress and a small rectangular fortress attached to the outside of the main fortress wall. There is also Eummaji, which includes four wells and two ponds. Inside the fortress are the remains of the Janggihyanggyo Local Confucian School and the old government office site. The main building of the old government office was moved to the Myeon-office and has been preserved there. Janggieupseong is a very important site for research on the fortress town in Korea because it was built at the summit of a mountain, serving not only as a military fortress but also as an administrative center of the region.