Florham is a former Vanderbilt estate that is located in Madison and Florham Park, New Jersey. It was built during the 1890s for Hamilton McKown Twombly and his wife, Florence Adele Vanderbilt, a member of the Vanderbilt family. Now part of the Florham Campus of Fairleigh Dickinson University, the mansion is one of the ten largest houses in …Florham is a former Vanderbilt estate that is located in Madison and Florham Park, New Jersey. It was built during the 1890s for Hamilton McKown Twombly and his wife, Florence Adele Vanderbilt, a member of the Vanderbilt family. Now part of the Florham Campus of Fairleigh Dickinson University, the mansion is one of the ten largest houses in the United States.