In order to create a public space for the local community, the downtown area of Seoul makes full use of the space under the viaduct. In crowded metropolises, this type of space is usually unusable. This project is an experimental project; it aims to transform the dark and cold space into vividness by transforming the passage under the viaduct to improve the living environment and the surrounding landscape.

The base is located in the space below the viaduct near the east gate. Above is the large-scale infrastructure, and the railway overpass and the highway overpass overlap on it. These viaducts isolate the scale of the city from the surrounding neighborhoods, and the area between them is isolated, like a static space where time stops. The project is committed to becoming the center of the local community, serving as a community space for different humanities and sports activities, using the architectural element "terrace" to connect the surrounding blocks in areas where no one cares about it.

The "Terrace Plaza" is a midline space, divided into upper and lower floors, using the roof to create a brand new public space. The space on the upper level is distributed east-west and ends at an elevated road. The lower space merges the surrounding blocks into the base and extends the base to the surroundings. The upper part of the terrace is used as a space for cultural activities, basic exercise, relaxation and entertainment; the lower part of the terrace is a place for local residents to escape the summer heat, and at night is an outdoor terrace cafe for nearby restaurants and vendors. The daily life of local residents is changing with time in the courtyard space of the "Terrace Plaza".