This unique design by Japanese firm Suppose Design Office is an ultra-modern take on traditional pit-dwelling houses. The main floor of the House in Saijo is partially underground, with the upper half of the walls comprised completely of glass. Looking as though it hovers above the ground, a large, dark pyramid shape encloses the second and third floors. Soil leftover from excavation of this site in Hiroshima was used to create a “fence” of a mound of earth that encloses the yard and provides privacy for the ground level. A skylight at the peak of the roof spills light through two sets of stairs all the way to first floor.