What is "sukjeongmun"

Sukjeongmun (Hangul 숙정문, Hanja 肅靖門; also known as North Gate) is one of the The Eight Gates of Seoul in the Fortress Wall of Seoul, South Korea, which surrounded the city in the Joseon Dynasty. The gate is also known as Bukdaemun (북대문, “North Big Gate”). It was built north of Seoul behind Gyeongbokgung Place. It was rarely used. It was only used in ceremonious and symbolic functions. To access it requires identification like passport.