The tunnel is part of the continuing development of the eastern area of Amsterdam and is situated in the midst of several new building projects. This project consists mainly of two small service buildings. These technical constructions each have a concrete core, enveloped by an asymmetrical skin of perforated steel plates and titlted roof planes. In conjunction with the general asymmetry this emphasizes the ‘un-architectural’, object-like character of the inaccessible service structures. Rather than real, lived-in buildings, these structures function as urban signposts for the tunnel entrances. These entrances are characterized by the simple application of profiled aluminium cladding. Steel beams are placed crossways over the sober concrete tunnel mouths.