The residential highrise tower by Francine Houben of Mecanoo is the counterpart for the free-standing office building, Foster's World Port Center. For Mecanoo it was important the contrast between the north and south sides should not be expressed in the way the buildings looked, and did not want to create a ‘housing project’ image. It consists of a composition of intersecting volumes, part of which is suspended above the quay. The construction contributes to the Holland-Amerika feeling: a system that alternates steel (Amerika), concrete (Holland) and then steel again. The first two floors are built of steel and bear the 152 meters high tower and the Water Apartments jutting 16 metres out. The 27 floors above are executed with a concrete climbing form. From the 28th floor steel is used. Windows, balconies and loggias are distributed in a rhythmic composition: corner-spanning, storey-high, circular, staggered, opening on hinges and sliding open.