Harlech Castle Walesissa oli Vanhan linnan salaisuuden, öh, linnan esikuva, tuunattuna.
Uncle Scrooge's castle at Dismal Downs is an amalgam of historic architecture.
The basic structure is that of Harlech Castle in Wales. To give the building a more antique air, Barks added turrets and battlements from Glamis and a tower of Cawdor, both Scottish castles which figure in the legend of MacBeth. Pictures of the "National Geographic Society" (the May 1946 and July 1947 issues) were used as source, they are reprinted in the The Carl Barks Library - Set I (page 1A-249).
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