Songwon Art Center in Seoul, Korea by Mass Studies:

The site is an irregularly shaped piece of land, roughly 297? in size, sitting in an entrance location to the Buk-Chon area when approached from the city center. The two adjacent roads meet in a sharp angle, with the main street sloping up towards the site. These situations give this small plot an unusually strong recognizability.

The massing of the building is largely limited by two conditions – the shape of the plot determined the plan of the building, and the adjacently located House of Yoon-Bo-Sun, a cultural heritage site, determined the elevation of the building to be cut in an angle in relations to sightline conservation. The volume trapped in these restrictive borders could only contain roughly two thirds of the maximum buildable floor area above ground (90% out of max. allowed 150% FAR). Therefore, much of the exhibition program had to be located below ground-level.

The resulting building is three floors below ground level and two floors above. The bottom two floors are used as an exhibition space, the semi-underground B1 level as parking, and the top two floors house a commercial restaurant and other social functions.

via ArchDaily