660 Fifth Avenue in New York, NY
Re-cladding of 660 Fifth Avenue Ramps Up in Midtown, Manhattan
660 Fifth Avenue - Wikipedia
Mrs. William K. Vanderbilt Mansion - New York City
File:Vanderbilt Mansion at 660 Fifth Avenue.jpg - Wikimedia Commons
Daytonian in Manhattan: The Lost Wm. K. Vanderbilt Mansion -- 660
Amidst Fifth Avenue renaissance, Saks Fifth Avenue partners with
660 Fifth Avenue - Wikipedia
Alva Vanderbilt and Richard Morris Hunt's white limestone
660 Fifth Avenue — Island Exterior Fabricators