The building complex is located in the mi ddle of the city center of Mainz, Germany. Its existing “historical” facade shown to the Cathedral in Mainz and its new facade to the Rebstockplatz compose the entrances to a halfclosed inner courtyard, a weather-protected “Piazzetta”. This was designed as a half-open, spatially graduated free space, which extends from the underground level over the ground level and the third level, including terraces and access level for the offices and residences, up to the glass roof.