The Poortgebouw was designed as the head office of the Rotterdam Trade Association (RHV). Originally two such gateway buildings were planned, one on each side of the bridge across Binnenhaven, to act as wind shields for passing ships. The second building was in fact built some years later only to be demolished in 1937 during operations to replace the bascule bridge. The building's original row of three portals was then reduced to a single wide opening. It has had a mixed bag of users over the years: the Holland-America Line (1880-1901), the Rotterdam branch of the Royal Dutch Meteorological Institute (KNMI, 1889-1950) and the Port of Rotterdam (until 1978). After briefly achieving notoriety as a potential 'erotic centre', it was allocated for housing in 1980.