The development consists of two U-shaped tracts, one enclosed at an angle within the other (see Detail 6/99). The resulting wedge-shaped glass-roofed hall spaces house the main vertical and horizontal circulation elements. These comprise free-standing lifts, balconies, bridges that link the two tracts, and a generous staircase that extends over the entire length and height of the northern hall. The staircase is articulated into a series of elements that span from floor to floor and from one bridge to the next. It also diminishes in width as it rises, thus reflecting the decreasing volume of traffic. The comfortable ratio of rise to going (15 : 31.5) is conducive to the relaxed, leisurely environment created here. The stairs are supported by sheaves of longitudinal steel beams, consisting of T-sections with tubular lower chords welded on, and with tubular bracing in the lateral direction. The beams diminish in number with the width of the stairs. The solid walnut steps are matched to the industrial parquet of the bridges.
