Darwin D. Martin House, in Buffalo, New York, is a must for any lover of Frank Lloyd Wright architecture. One of Wright's greatest works, this Prairie-style home was designed and constructed between 1903 and 1906. Wright imagined the 10,000-square-foot residence for Martin, who was one of Buffalo's wealthy industrialists and one of Wright's biggest boosters. Its low-slung profile with an emphasis on the horizontal was and remains an amazing piece of architecture. A tour of the inside reveals the architect's genius for expanding spaces and hiding bookcases.