BNSF 6962 (ES44C4) waits for the green light to muscle an oil can train towards Pinecliffe, Colorado on the Moffat Tunnel Sub.

BNSF 4419 (Dash9) runs long hood forward as it heads into the Denver Yard where it will be lashed to an awaiting train.

Here is a wide-angle view of the BNSF engine servicing facility in Denver, Colorado.

CAGX 1134 (SW1200) works a cut of cars at the Commerce City Grain silo in Commerce City, Colorado.

BNSF 6962 (ES44C4) waits at the signals in Tolland, Colorado for the green light to move a freight.

Heavy BNSF motors are repositioning in the engine servicing facility as they will soon get order to head to the yard for a train assignment.

The California Zephyr runs through Tolland, Colorado on a sunny day.

The California Zephyr passes through a crossing in Wiggins, Colorado at sunrise.

Amtrak engine #194 (P42DC) backs the California Zephyr into Union Station in downtown Denver, Colorado. The myriad of catenaries support RTD's Commuter Rail trains that also use the station.

A Union Pacific motor sits at the servicing island at the BNSF engine facility in downtown Denver, Colorado.

BNSF 2718 (GP 39-2) heads to the Denver Yard to start the day sorting cars.

The iconic Union Station in downtown Denver, Colorado is home to the California Zephyr which visits twice a day (the westbound train 5 in the morning and the eastbound train 6 in the evening).

BNSF 7911 (ES44DC) heads south on the Joint Line out of Denver, Colorado.

UP 1357 is a 51-year-old GP40-2 that was built in 1972 for the Rio Grande railroad.

BNSF 8415 (SD70ACe) leads a loaded coal train through Pinecliffe, Colorado on the Moffat Tunnel Sub.