UP heritage engine 1995 (SD70ACe) in the Chicago Northwestern livery waits for a crew that will take it up the Moffat Tunnel Sub.

UP 1381 (Ex Southern Pacific GP40-2) sits in the North Yard waiting for an assignment.

Snow and subfreezing temperatures blanket the Union Pacific's North Yard in Denver, Colorado.

A gathering of heavy power wait at the engine servicing facility for fuel, sand or a train assignment.

Light power dominates the Union Pacific's North Yard in Denver, Colorado. In years past these tracks were full of power and it was not uncommon to see 50 or more engines.

UP 801 (GP38-2) sits with other light power in the Union Pacific's North Yard in Denver, Colorado, waiting for the call to take its turn shuffling rolling stock.

A Ferromex engine sits at the BNSF engine servicing facility in Denver, Colorado, joining other BNSF power waiting for service or train assignments.

UP 1826 SD40N get ready to sort a string of cuts in the bathroom.

The flashing light on UP 845 (GP38-2) indicates that the tank is configured for remote operations.

Executive MAC BNSF 9709 leads the Beer Train through Denver and the North Yard.

A herd of 4 Norfolk Southern ponies join other BNSF motors as they wait for service or assignments at the engine servicing facility in Denver, Colorado.

BNSF 8417 (SD70ACe) leads a loaded coal out of the Denver Yard and heads towards the southbound track of the Joint Line.

DENVER CO Oct 20 1977 — Colorado and Southern-Santa Fe SW1200 157 slowly heads for a cut of cars while performing switching duties. At the time the unit was jointly operated by C&S and Santa Fe.... (more)

An Executive Grinstein SD70MAC leads a long beer train destined for the Coors Brewery in Golden, Colorado.

It is a packed house as heavy and light motors congregate at the engine servicing facility in Denver, Colorado.