Lever House
Lever House is located at 390 Park Avenue between 53rd and 54th streets and is commonly regarded as the quintessential representative of "International Style" architecture. Designed by Gordon Bunshaft of Skidmore, Owings and Merrill and built in 1951 - 1952, Lever House was the first of many "curtain wall" buildings in New York City, where the exterior walls bear no building load and are hung on an interior supporting building structure. The building is distinguished by its blue-green glass facade and public courtyard.
Lever House was built to be the American headquarters of the British soap company Lever Brothers although parent company Unilever had moved all of their operations out of the building to Englewood Cliffs, NJ by December of 2004. The building was designated an official landmark in 1992 by the New York City Landmarks Preservation Commission. The building underwent an extensive restoration in the late 1990s to replace the deteriorated steel subframe and correct other design deficiencies so endemic to mid 20th century American architecture.
While my tastes favor the more sturdy and ornamental Art Deco and Beaux-Arts styles, I must admit that Lever House is about as attractive a building as can be built within the constraints of the International Style.