BNSF 9232 (SD70ACe) muscles a coal train through Little Ten Curve at Rocky, Colorado.

A train of tank cars led by UP 5402 has passed Hot Sulphur Springs, CO and is now heading for Granby on its way to Denver.

BNSF 6077 (ES44AC) climbs the 2% grade out of Coal Creek Canyon and towards Tunnel #1 at Plainview, Colorado.

Rail Train at Tunnel 29 Relentless maintenance never ends on the Moffat Road. Rail being moved from Bond to Plainview passes through Cliff on a snowy morning in April.

The back end of an oil can train just passes Blue Mountain Road as the lead motor UP 6356 (AC4400CW) gets ready to enter Tunnel #1, the first of 28 tunnels on the Moffat Tunnel Sub.

A Union Pacific's officer's train runs through the S curve leading to Rocky, Colorado as it heads west on the Moffat Tunnel Sub.

UP 6045 (AC4400CW-CTE) leads an officer's special up the 2% grade out of Coal Creek Canyon and towards Tunnel #1.

BNSF 9232 (SD70ACe) runs an oil can train through Little Ten Curve at Rocky, Colorado.

Amtrak engine #39 (P42DC) runs through Rollinsville, Colorado as it heads west on the Moffat Tunnel Sub.

The California Zephyr #6 train drops down from Tunnel #1 and into Coal Creek Canyon.

The California Zephyr 6 train drops down the 2% grade into Coal Creek Canyon, Colorado as it heads to Denver on the Moffat Tunnel Sub. Denver's skyline is visible in the upper part of the photo. ... (more)

Rocky Mountaineer's GP40-3 leads the passenger train through Tunnel 14 in South Draw on the Moffat Tunnel Sub.

Storm clouds build overhead as the California Zephyr climbs out of Coal Creek Canyon towards Tunnel #1.

The California Zephyr runs a long consist through the Tollan Valley as it heads west towards the Moffat Tunnel and the Colorado Rocky Mountains.

The California Zephyr with 3 engines, 9 passenger cars, and a baggage car exits the east portal of Tunnel #1 at Plainview, Colorado as it heads west on the Moffat Tunnel Sub.