The covers of Great Northern’s timetables had been predominately orange since 1947 when it introduced the streamlined Empire Builder. They stayed orange, with F-unit locomotives replacing E units, when the dome cars were introduced in 1955.
The problem with this timetable cover is that it doesn’t actually show the dome cars that it advertises. That was a significant fault considering Northern Pacific featured the interior of a dome car on its timetable cover. As a result, in 1957 GN would change to a predominately blue cover that featured the Western Star and dome-laden Empire Builder passing in the mountains.