Seodaemun Prison is a modern prison built by Japanese imperialism.

It was used as a prison for 80 years, opening in October 1908 and closing in November 1987.

The prison was built with red bricks and designed in a panopticon structure, allowing for effective surveillance of the inmates.

This is a historical site where many anti-Japanese independence activists who resisted colonial rule were imprisoned during the Japanese occupation, and where pro-democracy activists who opposed dictatorial and military regimes were imprisoned after liberation.

The name has changed several times: Kyungsung Prison in 1908, Seodaemun Prison in 1912, Seodaemun Correctional Facility in 1923, Seoul Correctional Facility in 1945, Seoul Prison in 1961, and Seoul Detention Center in 1967. After the Seoul Detention Center moved to Uiwang City in Gyeonggi Province in November 1987, considering its historical significance and preservation value, security facilities, the main building, Blocks 9 to 12, the workshop, the leprosy ward, and the execution site were retained while the rest of the facilities were demolished.

Later, on November 5, 1998, the Seodaemun Prison History Hall was opened in Seodaemun-gu to preserve the site and learn from history. It operates as a museum that remembers and commemorates the beliefs of independence activists and democracy movement leaders in their pursuit of freedom and peace, using the lessons of the past.