Unloading cans of milk from early morning "milk run" train at Montrose, Colorado, in September of 1940.
A Milk Run is a trip or activity which can accomplished at a leisurely pace and with little effort. A routine and uneventful trip, especially on a dangerous mission. A milk run was originally a railroad train that progressed slowly, stopping at every farm along the way to pick up cans of milk for delivery to the local creamery. [When I was a kid, I actually rode a "milk run" train a couple of times.]
"Sure, the ride to Deadwood has its share of bandits, but to me it's just another milk run."
Photo by Russell Lee, courtesy of Library of Congress, Prints & Photographs Division, FSA-OWI Collection, reproduction number LC-USF34-037657-D DLC.