Jon,
I double checked. There is just a hand written note on the card, written by the person whose family donated it, that says "bought in 1971." I don't see any copyright date. Card could have been printed before 1971.
Caption reads, "The last of the narrow gauge trains, this excursion train runs the summer on special ocassions only, between Alamosa and Durango, Colorado." Photo by Digerness.