UP 8147 (ES44AC) leads a coal train through a snow-packed Coal Creek Canyon, Colorado on the Moffat Tunnel Sub.

UP 6825 (ES44AC) runs through dense fog at Coal Creek Canyon, Colorado on the Moffat Tunnel Sub.

UP 6825 (ES44AC) leads a freight south on the Moffat Tunnel Sub through Leyden, Colorado.

UP 2698 (ES44AC) runs south through Leyden, Colorado on the Moffat Tunnel Sub.

UP 6603 (AC4400CW) shoves a loaded oil can train through Plainview, Colorado on the Moffat Tunnel Sub.

Coors Brewery's SW1001 moves a cut of special grain hoppers towards the massive facility in Golden, Colorado.

The California Zephyr runs through a dynamic sunrise at Keenesburg, Colorado.

The California Zephyr is led by engine #82 in the recently applied Phase VII paint scheme. Here it runs over Highway 72 in Coal Creek Canyon, Colorado.

BNSF 8348 (SD70ACe) emerges like a ghost out of heavy snow and leads a stack train north on the Joint Line towards Denver, Colorado.

The BNSF yard in Denver is often home to some vintage SD40-2 motors, including on this day #1933, which was built in 1979 and still represents the Cascade Green fallen flag of the Burlington North... (more)

An Executive Grinstein MAC sits amongst the pumpkins waiting for service at the engine facility in Denver, Colorado.

The California Zephyr gets ready to climb up to Tunnel #1 after running through Coal Creek Canyon on the Moffat Tunnel Sub.

Amtrak engine #23 leads the Winter Park Express Ski Train through heavy snow at Coal Creek Canyon, Colorado.

UP 8435 (SD70ACe) leads a coal through Plainview, Colorado on its way to Denver.

UP 5567 (AC4400CW-CTE) muscles a freight through Little Ten Curve at Rocky, Colorado.