Union Pacific locomotive 5388 brings up the rear of a southbound coal train in Colorado Springs, CO on July 9, 2016.

A set of 3 GE locomotives lead a loaded coal train south through Colorado Springs, CO on July 9, 2016.

Basking in the late afternoon light, BNSF locomotive 9032 leads a southbound coal train through Palmer Lake, CO on June 11, 2016.

Durango & Silverton locomotive 481 rests at the Durango, CO station moments before departing for Silverton on May 10, 2016.

On a clear Friday, February 26, 2016, Amtrak's eastbound California Zephyr cruises through New Castle, CO.

A westbound manifest freight train rolls through Gore Canyon near Kremmling, CO on February 13, 2016.

With Little Gore Canyon in the background, a westbound manifest freight train cruises alongside the Colorado River shortly before passing through Bond, CO on February 13, 2016.

Running on time, the westbound California Zephyr rolls along next to the Colorado River just east of Burns, CO on February 13, 2016.

Approaching a short tunnel, Union Pacific locomotive 8261 leads a westbound manifest freight train near Radium, CO on February 13, 2016.

The westbound California Zephyr winds its way through one of the canyons a few miles southwest of Burns, CO on January 23, 2016.

The eastbound California Zephyr cruises through a sandstone canyon alongside the Colorado River, having just passed through the community of Burns, CO on January 23, 2016.

ES44AC number 7364 leads a long string of locomotives on a westbound power move a few miles southwest of Burns, CO on January 23, 2016.

An SD70AH brings up the rear of a consist of locomotives running light through Glenwood Canyon during the last moments of sunlight in Glenwood Springs, CO on January 17, 2016.

Amtrak train 5, the westbound California Zephyr, cruises along next to the Colorado River just after its stop in Glenwood Springs, CO on January 17, 2016.

Amtrak train 5, the westbound California Zephyr, rolls through Glenwood Canyon just before its stop in Glenwood Springs, CO on January 17, 2016.