Glensheen Historic Estate Glensheen, Duluth's American Castle, as showcased on A&E's America's Castles, is a 7.6 acre estate built between 1905-08 by Chester A. Congdon. First opened to the public in 1979, Glensheen resembles an English, early seventeenth century country estate. The focal point of English estates were the manor house which were located near the center of the property. Formal gardens dotted the grounds and added color. What is phenomenal about Glensheen is that, to this day, it closely resembles the way it looked when the Congdon family first moved in on November 24, 1908. The majority of the furnishings are original to the time the estate was first occupied. North Shore Scenic Drive