Danish Airlines DDL The Viking LinesOriginal vintage travel advertising poster for DDL Det Danske Luftfartselskab Danish Air Lines The Viking Lines featuring a great illustration of a white and red propeller plane with DDL marked on the wing and Viking on the side flying against a blue sky background above a traditional wooden Viking ship with a red and white striped sail at sea against a sunset sky between the diagonal blue and red lettering with the DDL title and logo of a bird flying