An advertising card, professionally prepared and mailed (as this one was) with Bulk Rate pre-printed postage.  The caption — being advertising, after all — is extensive and persuasive.  We were curious, and checked online, to find it still exists as a “census-designated place”, whatever that means, and one source wrote:  “When it was created in the 1960s, Rancho Calaveras was the largest residential subdivision in the state of California.”  For the postcard, Grade: 3