AMTK 198 (P42DC) skirts the base of Blue Mountain as it heads into Coal Creek Canyon on the Moffat Tunnel Sub.

UP 7801 (ES44AC) leads a train through Little Ten Curve at Rocky, Colorado.

UP 1507 (GP40M) passes the Union Pacific's operations building at the North Yard in Denver, Colorado.

UP 9581 runs into light snow showers as it exits the east portal of the Moffat Tunnel with an oil can train.

As a passenger watches out the rear window, the California Zephyr 5 train gets ready to enter the east portal of the Moffat Tunnel.

As light snow falls over Denver, Colorado, the California Zephyr 5 train gets ready to back into Union Station, which sits amongst the high-rise buildings.

It seems the California Zephyr is destined to be led by a pair of Phase VII P42's. This colorful consist is a welcomed addition for photographs along the Moffat Route.

The California Zephyr 5 train has left Denver and is running towards Rocky, Colorado on the Moffat Tunnel Sub.

Long live the Warbonnet! BNSF 704 (Dash9) pulls up for service at the engine facility in Denver, Colorado.

UP 8714 (SD70ACe) exits the Hermosa Tunnels hauling a heavy transformer towards Laramie, Wyoming.

The California Zephyr 5 train runs through Keenesburg, Colorado at sunrise.

Here we get a good look of the new Phase VII paint scheme that has started to grace the P42DC's as the California Zephyr 6 train runs past the BNSF's intermodal facility in Denver, Colorado.

The California Zephyr 6 train rousts the pigeons as it runs past the Union Pacific's North Yard in Denver, Colorado.

Dynamic weather moves in over the mountains at Plainview, Colorado as UP 5624 (AC4400CW-CTE) leads a freight through Rocky on the Moffat Tunnel Sub.

BNSF 6339 (ES44AC) exits Tunnel #1 and will drop down into Coal Creek Canyon, Colorado on its way to Denver.