A westbound Union Pacific coal empty climbs through the Tunnel District at South Draw just east of Crescent, Colorado, on May 14, 2017. The train snakes through five tunnels at once, twisting thro... (more)

On the afternoon of June 16, 2017, a long train of military equipment from Fort Carson, near Colorado Springs, Colorado, heading to Yermo, California, is westbound on Union Pacific’s Moffat Tunn... (more)

With the Continental Divide looming above, a loaded Rio Grande coal train arcs through the long curve at Crescent, Colorado, in July 1984.

Climbing upgrade through the Tunnel District east of Crescent, Colorado, a westbound Union Pacific train blasts out of Tunnel 12 with a cloud of smoke on the afternoon of June 16, 2017. Leading th... (more)

A heavy train of military equipment from Fort Carson, near Colorado Springs, Colorado, heading to Yermo, California, is westbound on Union Pacific’s Moffat Tunnel Subdivision on June 16, 2017. I... (more)

The power on a westbound Union Pacific coal train exits Tunnel 13 in Tunnel District at South Draw just east of Crescent, Colorado, on May 14, 2017.

AMTK 406 in its CenturyLink wrap rounds the curve at Crescent Siding as the westbound Winter Park Express continues its trip up to the Winter Park Ski Resort.

Amtrak coming through the hills of Colorado.

A westbound Union Pacific coal train climbs through the tunnels at South Draw just east of Crescent, Colorado, on May 14, 2017. In this view, the train is exiting Tunnel 12, threading Tunnel Nos. ... (more)

Deep in the Tunnel District between Plainview and Crescent, Colorado, Amtrak’s eastbound California Zephyr threads through Tunnel 15 on May 14, 2017.

Heart of the Tunnel District
A westbound Union Pacific coal train climbs through the heart of the Tunnel District at South Draw just east of Crescent, Colorado, on May 14, 2017. The trai... (more)

The sun is setting into a western sky thick with clouds over Colorado’s jagged Continental Divide as a Union Pacific coal train drops downgrade at Crescent at 7:42 p.m. on May 14, 2017.

A momentary spotlight of sunshine illuminates an eastbound BNSF freight leaving Crescent, Colorado, on May 11, 2001. Fully lit in the background is the snow-covered Continental Divide.

Union Pacific’s MRONY (Salt Lake City’s Roper Yard to North Yard in Denver) freight curves through Crescent, Colorado, on March 28, 2016.

Union Pacific MDVRO (Denver to Salt Lake City) works upgrade out of Tunnel 18 at Crescent, Colorado, on the afternoon of May 23, 2001.