Geumseongsanseong Fortress in Geumseongsan Mountain (603m) forms a boundary between two small villages located on the border of two provinces (Geumseong-myeon, Damyang-gun, Jeollanam-do and Sunchang-gun, Jeollabuk-do) and is one of the three popular mountains of the Honam region (the Southwestern region of Korea that includes Jeollanam-do and Jeollabuk-do). The fortress is surrounded by two walls connecting Cheolmabong Peak, Undaebong Peak, and Jangdaebong Peak. The total length of the outer wall is 6.486 meters and inner wall is 859 meters.

Historians are uncertain about the year the fortress was built, and have concluded that it dates back to the Three Kingdoms Period (57 BC – 676 AD) based on an examination of the ruins and remains discovered in the surrounding area. The fortress was reconstructed in 1409 and repaired in 1610 after the Imjin War (1592-1598). Following that, it continued to develop into a strong military base.

- Classification: Historic Site No. 353
- Date of Designation: August 24, 1991
- Owner: Park Jinseong and 85 persons
- Age: Three States Era
- Site Area: 1,349,977㎡
- Kind of Cultural Properties: Castle Site