A town fortress was built in a town where a local government office was located. It was used not only as an administrative office but also as a military base. Normally, it served as an administrative office as well as the defensive fortress in times of emergency. Haemi was the military base center from the 14th year of the reign of King Taejong (1414) to the 2nd year of the reign of King Hyojong (1651). This fortress started to be constructed during the reign of the Great King Sejong, and it was completed in the 22nd year of the reign of King Seongjong (1491). This fortress, originally built to protect against Japanese pirates, was a historical site where thousands of Catholics were executed during the French Invasion in 1866. Rev. Kim Dae-geon was said to have been martyred here. It reportedly had another name -- trifoliate orange tree fortress -- since it was surrounded by trees. Including the magistrate's offices, some relics related to Catholic persecution remained. Among the east, west, and south gates, Jinnamnu, the south gate, had been preserved; the east and west gates were reconstructed in 1974. The facilities in the fortress were unearthed and were under investigation in 1980 and 1981. This was the most representative town fortress among the existing ones.