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.

Rocky Mountaineer's 8021 (GP40-3) leads the passenger train through Tunnel #15 in South Draw, Colorado as it heads to Denver on the Moffat Tunnel Sub.

BNSF 8537 (SD70ACe) runs through Tunnel #29 at Pinecliffe, Colorado.

The California Zephyr #6 runs through an S curve cut in Crescent, Colorado as it heads into South Draw on the way to Denver.

UP 8697 (SD70ACe) leads a coal train down the 2% grade at Eisele, Colorado as it runs towards Denver on the Moffat Tunnel Sub.

The Rocky Mountaineer passenger train gets ready to enter Tunnel #14 as it runs through South Draw on the Moffat Tunnel Sub in Colorado.

The Rocky Mountaineer passenger train runs through Tunnel #15 in what is arguably the most scenic part of the Moffat Tunnel Sub. The area known as South Draw affords views of 5 tunnels, providing... (more)

BNSF 4404 (Dash9) exits Tunnel #13 deep in South Draw as it leads the California Zephyr west on the Moffat Tunnel Sub.

BNSF 4404 (Dash9) runs through Tunnel #14 as it leads the California Zephyr into South Draw on the Moffat Tunnel Sub.

BNSF 4404 (Dash9) leads the California Zephyr through tunnel 12 as it runs through South Draw, Colorado on the Moffat Tunnel Sub.

BNSF 4404 (Dash9) leads the California Zephyr through Tunnel #13 on the Moffat Tunnel Sub. The Zephyr lost an engine and picked up the BNSF helper in order to traverse through the Colorado Rocky ... (more)

BNSF 4404 (Dash9) leads the California Zephyr #5 train through South Draw on the Moffat Tunnel Sub. The train lost an engine in Fort Morgan, Colorado and needed a little help getting through the ... (more)

BNSF 5146 (Dash9) rounds the Big Ten Curve at Rocky, Colorado as it heads down the 2% grade towards Denver.