Summit Hotel, undated postcard.

The Summit Hotel (completed 1961) was the first major New York project for architect Morris Lapidus. Known for his oversized and somewhat garish Miami hotels (the Fontainebleau Hotel, particularly), Lapidus introduced a new type of building geometry to the staid rectangular forms of midtown. The 51st Street frontage is rendered as a subtle curve, with a uniform facade pattern of windows tucked between protruding white-brick masonry. Architectural critic Ada Louise Huxtable said of the hotel: ''The Summit is a glittering display of gaudy confusion...[m]osaics, marbles, woods, enamels, fabrics, synthetics, colors and crafts have been poured forth and combined with profligate abandon and aggressive insensitivity.'' Others have described it as jolly and welcome surprise among the city's grid.

The architect himself noted many years after its completion that it was the "most hated" hotel in the city. But despite its scorn, it can be credited with—if not directly inspiring other eclectic building— at least laying the foundation for later experiments in architectural geometry. The hotel has changed hands a number of times in the last few decades and has had extensive alterations. Today it is the DoubleTree by Hilton Hotel Metropolitan. While many of the more ostentatious features have been removed or toned down, the groovy eight-story sign on the Lexington Avenue facade, which now spells out Doubleday on its oval protrusions, remains.