Sewoon Sanga is a 1.2 km megastructure in the heart of Seoul designed in 1967 as part of the Sewoon Sanga Project. It is located in the centre of Seoul's historical district in Jongro-gu and Jung-gu, which consists of seven shopping centres (sangga means shopping centre) stretched across more than kilometer from Jong-ro, Chenggyecheon, Eulji-ro, Mareunnae-ro and Toegye-ro. To the north is Jongmyo, a UNESCO World Heritage site.

The land on which the complex was built was left as an empty lot during the JApanese colonial era towards the end of WWII to prevent fires by bombings from spreading in the city. when the Korean War began regugees started squatting, creating a substandard living district. The currewnt Sewoon Sanga complex was deigned by achitect Kim Swoo Geun in the late 1960y under Korea's first downtown redevelopment programme.

Sewoon Sanga was conveived as a multi-layered city with a separation of pedestrians and car traffic. It is a mixed use building which combines commercial spaces, offices and residential quarters. The amenities were outstanding at the time and the building gained popularity among noted public figures.