Collinwood was the home of the Collins family, overlooking the town of Collinsport, Maine. A huge mansion, its grounds were evidently large enough one needed a car to travel from the main mansion to the Old House. As portrayed, it came across as a place filled with long corridors.
Greystone Mansion in Beverly Hills was used as a stand-in for Collinwood while filming the Dark Shadows (2004) pilot.