3. The Vanderbilt Triple Palace: 640 and 660 Fifth Avenue and 2 West 52nd Street
These “Triple Palaces” were built by William Henry Vanderbilt bought an entire block between 51st and 52nd Street where he built the three near-identical brownstone homes for himself and his wife along with their two daughters, Emily and Margaret. The adjoining drawing rooms could be converted into one large ballroom when needed. Though William H. Vanderbilt’s will barred the home from being sold outside of the family, a loophole was found and the property ended up in the hands of the Astors. The Astors unloaded the estate in the 1940s and today it is occupied by skyscrapers and retail.