An old EMD E-9A, built in 1961. Electro-Motive's E series (and it's cousin, the F-series freight engine) is an icon of American railroading. Built between 1937 and 1963, these cab units (so named because of the car-like shape to their noses) were easy to use and maintain, and their ease of being run in tandem revolutionized railroading. They also proved to be long-lasting-E-series passenger units were still being used in commuter service into the early 1990's, and plenty of short lines continue to use them today, almost fifty years after production ceased.
This late example is a former Milwaukee Road unit, and is on display at the Illinois Railway Museum.