1251 Avenue of the Americas

1251 Avenue of the Americas, formerly known as the Exxon Building, is a skyscraper on Sixth Avenue in Manhattan, New York City, between 49th and 50th Streets. It is owned by Mitsui Fudosan. The structure is built in the international style and looks like a simple cuboid devoid of any ornamentation. The vertical façade consists of alternating narrow glass and limestone stripes. The glass stripes are created by windows and opaque spandrels, forming continuous areas that are washed by machines sliding down the façade. A seven-floor base wraps around the western portion of the building, and there is a sunken plaza with a large two-tier pool and fountains facing Sixth Avenue. In the plaza stands the bronze statue named Out to Lunch by John Seward Johnson II—of the same series as the one standing outside the 270 Park Avenue.
The building was part of the later Rockefeller Center expansion dubbed the "XYZ Buildings". Their plans were first drawn in 1963 by the Rockefeller family's architect, Wallace Harrison, of the architectural firm Harrison & Abramovitz. Their letters correspond to their height. 1251 Avenue of the Americas is the "X" Building as it is the tallest at 750 ft and 54 stories, and was the first completed, in 1971. The "Y" is 1221 Avenue of the Americas, which was the second tower completed and is the second in height . The "Z" Building, the shortest and the youngest, is 1211 Avenue of the Americas with 45 stories . 1251 is the second-tallest building in the whole of Rockefeller Center, after 30 Rockefeller Plaza.

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