When Gordon Bunshaft of Skidmore, Owings & Merill built Lever House in 1952, Park Avenue was lined with solid masonry buildings, packed one against the other, all pushed to the street's edge. The Lever Brothers (manufacturers of soap and detergents) erected the boulevard's first glass-covered office tower. The tower stands with its narrow side towards the street. The slab is counter-posed to a horizontal slab which floats on a series of columns. The horizontal mezzanine is cut out in the center, creating a central courtyard. Now, 50 years later, Lever House stands as a model of intelligent architecture, and with it current landmark restoration, it shines brighter than ever. The restoration holds as closely as possible to the original. It is a small building by Manhattan standards, but the glass-walled skyscraper marked a turning point in American office architecture. The fact that the tower now seems like just one of so many office towers shows how much it has been copied.