The Koshino House in Ashiya, Japan was designed by renowned architect Tadao Ando in 1980-1984. The house consists of two parallel cubic volumes connected by an underground tunnel. Concrete was the primary material used to create the smooth, corrugated surfaces of walls, floors and ceilings. Large windows made of glass allow natural light to flood the interior spaces. The design incorporates principles of Brutalism, asymmetry, repetition and blending of interior and exterior spaces.