6. The Bostwick Mansion, 800-802 Fifth Avenue
Jabez A. Bostwick made his fortune with Standard Oil and used it to build a 10-room French Second Empire mansion in 1876 on the corner of 61st Street. After Jabez’s death, his wife Helen lived in the home until she too passed away in 1920. Family friend Mrs. Marcellus Hartley Dodge, a daughter of William Rockefeller purchased the Helen Bostwick home in 1922 and left it seemingly abandoned until 1977. In 1979, the Gilded Age mansion was demolished to make way for a 33-story luxury apartment building.