Introduction to Nampo Eupseong Fortress
- Quantity/area: 105,283㎡
- Period : Joseon Dynasty
- Owner: Boryeong City
- Manager: Boryeong City
- Designated: Provincial Monument (24 December 1973)

A 邑 castle is a castle that protects the residents of a county or county and serves both military and administrative functions. Nampo Eupseong is a castle made of stones in a hill at the western end of the Charyeong Mountains, and Nampo was also called Sapohyeon during the Baekje period. This castle was originally built during the reign of King Wu of the Goryeo Dynasty to prevent Japanese pirates from invading the west coast, but it was completed by adding a camp where the army could stay in the 2nd year of King Gongyang (1390). The walls of the castle remain relatively well, with the outer walls stacked at right angles using stones, and the inside of the castle walls stacked with soil.
The Ongseong Fortress, another wall placed outside the castle at a height of 4 m to protect the gate, was constructed from a large stone over 1 m in the three East, West, and South locations. In the area where the wall is bent, some of the walls are stacked to protrude so that you can quickly observe the enemy's approach, and several facilities are installed to hide themselves on both walls and attack them. In the castle, three government buildings, Jinseoru, Naesammun (Oksanammun), and Oedongheon, are preserved, and drainage facilities are installed at a height of 80 cm from the east and west. Records show that there were three wells. This town is considered to have played a role in protecting and monitoring maritime traffic while guarding the Japanese pirates as a key point on the west coast.