With the city of Denver and the plains of eastern Colorado in the background, a BNSF manifest freight departs Rocky on the clear afternoon of June 28, 2014.

Afternoon sun glints off the last cars of a late-running Amtrak No. 5 as it climbs out of Rocky, Colorado, on December 5, 2014.

Union Pacific’s west local has just come off of Rocky Spur and slowly heads east on the main while a westbound coal train passes on the siding at Rocky, Colorado, on March, 16, 2011.

In March of this year Amtrak did a trial run of the legendary Ski Train which shuttled skiers from Denver's Union Station to Winter Park in the morning and then back again in the evening. The tes... (more)

AMTK 93 has just rounded Big 10 Curve and heads towards tunnel No 1 on the Moffat Line. Notice anything missing?

As the rear of an eastbound Union Pacific coal train heads through Rocky, Colorado, below—an eastbound BNSF manifest freight passes through Tunnel 1 in the background on August 11, 2015. The rea... (more)

As the sun sets behind the front range of the Rockies, a westbound Union Pacific coal train negotiates Big 10 Curve between Rocky and Eisele (formerly Clay), Colorado. The City of Denver can be se... (more)

Amtrak’s westbound California Zephyr climbs the front range of the Rockies as it leaves Rocky, Colorado, and heads toward Big 10 Curve on August 11, 2015.

A patched SP unit brings up the rear of the Denver - Salt Lake City manifest at Rocky, CO.

The westbound California Zephyr starts its climb up the Rocky Mountains as a dense patch of fog begins to lift along the foothills.

Another loaded coal train descends around the Big 10 curve.

Two clean Union Pacific GEs lead the eastbound UP coal train that is exiting Big 10 Curve and heading for Rocky, Colorado, seen directly above the locomotives on August 11, 2015. Above the lead lo... (more)

As a Union Pacific coal train drops downgrade approaching Rocky, Colorado, the lone DPU holds back the train near the east switch at Eisele (formerly Clay), Colorado, on August 11, 2015. When watc... (more)

The lead locomotives of an eastbound Union Pacific coal train are about to take down the signals at the west end of Rocky, Colorado, on August 11, 2015, as three mid-train DPUs pass by just moment... (more)

The lone DPU on the rear of an eastbound Union Pacific coal train features a surviving Southern Pacific locomotive west of Rocky, Colorado, on August 11, 2015. SP GE AC4400CW No. 335 is one of onl... (more)