Art Burrill's collection Part Two
In the late 1950's time frame, UP began to run heavy steam freight power out of Denver northward as diesels displaced them on the Overland Route. These two photos show Big Boys 4010 and 4012 speeding through Eaton in freight assignments, headed northward.

Big Boys are thought by many to be among the largest steam locomotives ever built. They were the largest on Union Pacific. None are operating at the moment, but one such locomotive is UP4005, Jack Forney's locomotive which is in transit to the new Forney museum in Denver at this time.

[Page three of Vol 2. Art Burrill's Pictures]