c1906 Picture Postcard - Round-Up & Mess Wagon - Dickinson, North Dakota. #-7749. Vintage Picture Postcard is selling as a used standard size postcard. Unused Vintage Picture Postcard shows some light wear. Postcard measures: 5-1/2" x 3-1/4". Nice Vintage Real Picture Postcard of a Round-Up near Dickinson, North Dakota. See pictures for condition information and card details. Item will be shipped in a non-machinable ridged mailer. I do combine shipping.