The California Zephyr 5 train leaves the Denver skyline behind (in the upper right) and passes through Leyden, Colorado on its way up the Moffat Tunnel Sub.

The California Zephyr runs between Tunnels #1 and #2 as it passes through Plainview, Colorado.

BNSF 6012 (ES44AC) shoved a coal train past a waiting UP freight train waiting on the siding at Plainview, Colorado.

Plainview BNSF MPVODEN nears Denver through Plain.

UP 6789 (AC4400CW) leaves Plainview, Colorado as it heads towards Tunnel #1 and Coal Creek Canyon.

UP 6789 (AC4400CW) sits among the wild sunflowers at Plainview, Colorado, waiting for a BNSF coal train to pass on the main track.

With the Boulder Flatirons in the background, a UP crewman walks back to his motor as BNSF 6012 (ES44AC) passes and heads up the Moffat Tunnel Sub.

UP 6454 AC4400CW leads an officer's special down the hill into Coal Creek Canyon, Colorado as it heads to Denver.

UP 6454 AC4400CW exits Tunnel #1 at Plainview, Colorado and will drop down into Coal Creek Canyon.

UP 6789 (AC4400CW) meets a BNSF coal train at Plainview, Colorado.

UP 6789 (AC4400CW) waits on a siding at Plainview, Colorado for a BNSF coal train which will be passing shortly.

UP 5889 (AC4400CW-CTE) leads a coal train up to Tunnel #1 at Plainview, Colorado as it heads west on the Moffat Tunnel Sub.

AMTK 135 (P42DC) leads the California Zephyr down the hill into Coal Creek Canyon as it heads to Denver, Colorado.

The California Zephyr runs between tunnels 3 and 4 as it begins the climb up the Moffat Tunnel Sub to the Continental Divide.

The sounds of GE motors echo through Coal Creek Canyon as they work their train out of the Big 10 Loops and up the grade around Plainview, CO on Union Pacific’s iconic Moffat Tunnel Subdivision.... (more)