A prototype for the coexistence of Muslims and non-Muslims in Germany, the Center’s main elements are grouped around a raised public plaza, reached by a wide stair. Beneath, at street level, are a bazaar and conference room. The library, offices and museum framing two sides of the plaza reflect the existing urban fabric in height and massing; but the domed prayer-hall that dominates the third side stands out. Its series of concrete shells are linked by recessed vertical bands of glazing in a play of solid and void. The concrete surfaces are roughed to recall stonemasons’ work. Over 70% of the energy needed for heating and cooling is derived from on-site geothermal resources.