It is hard to stand out in the Back Bay with rows of stunning townhouses, but the Bates Mansion does just that. Attributed to Arthur Gilman, a prominent Boston architect, the home was built for John D. Bates and his wife, Mary, who was related to the architect by her first marriage. Mr. Bates – a shipping merchant dealing in the sugar trade also served as Danish Consul in Boston – died in Europe in 1863, leaving Mary and their son, to live at the magnificent structure until 1865, when they downsized. After subsequent ownership, the property was purchased by the Roman Catholic Archbishop of Boston in 1947, combined with the adjacent property, and converted to a day school and convent. The combined structures were later purchased by developer in the 1990s and transformed into nine condominium units. The massive Second Empire mansion was the first building constructed in Boston using Acadian freestone and features a projecting central bay over the entrance supported by Corinthian columns.