Gilded Age Mansions Line The Avenue. It is The Only Block in New York City Not Where There Is Not One Commercial Building. This is because of regulations put in place by Henry Cook, allowing no commercial buildings.
666 Fifth Ave. | New York, NY. Virginia Vanderbilt Mansion. Built where 2 brownstones once stood and connected to the original William K. Vanderbilt, Sr. mansion beside it. It was demolished to make way for an office building which was itself demolished for the present office building.