Andrew Carnegie Mansion

The Andrew Carnegie Mansion is a historic house located at 2 East 91st Street at Fifth Avenue in the Upper East Side of Manhattan, New York City, New York. Andrew Carnegie moved into his newly completed mansion in late 1902 and lived there until his death in 1919; his wife, Louise, continued to live there until her death in 1946. The building is now the Cooper-Hewitt, Smithsonian Design Museum, part of the Smithsonian Institution. The surrounding area, part of the larger Upper East Side neighborhood, has come to be called Carnegie Hill. The mansion was named a National Historic Landmark in 1966.
The land was purchased in 1898 in secrecy by Carnegie, more than a mile north of what was then fashionable society, in part to ensure there was enough space for a garden. He asked his architects Babb, Cook & Willard for the "most modest, plainest, and most roomy house in New York". However, it was also the first American residence to have a steel frame and among the first to have a private Otis Elevator and central heating. His wife, Louise, lived in the house until she died in 1946.

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