Designed by Loewer+Partner, this gymnasium near Frankfurt only keeps a low profile in the literal sense; its unique design has made it stand out as a local landmark. Loewer+Partner beat out twenty firms with a design that buries a local school's indoor athletic area. Anyone passing by can become a spectator thanks to glass walls that wrap around the arena, which is submerged about ten feet below ground level. Thick wooden beams support the roof while keeping the playing field totally open. This subterranean design is certainly novel but also environmentally friendly: Thanks to the insulating properties of soil, the building costs less to heat in winter and cool in summer.