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.

A pair of Union Pacific AC motors lead a loaded coal train into the siding at Crescent while a track guy worked on the main. The train would soon meet Amtrak #5 at Plain.

A summer edition of the Rio Grande Ski Train climbs out of West Crescent, Colorado, on July 21, 2001. New signals replacing the Denver and Salt Lake Railway-era searchlights are in place, and the ... (more)

Union Pacific MDVRO (Denver to Roper Yard) manifest storms out of Tunnel 18 east of Crescent, Colorado, on August 25, 2001. Lead locomotive UP No. 4766 is a former Southern Pacific SD45 that SP re... (more)

Rio Grande EMD SD40T-2 Tunnel Motor No. 5401 leads Union Pacific’s MDVRO (Denver to Salt Lake City) manifest freight rumbling through Crescent, Colorado, on April 2, 2001. This locomotive has be... (more)

A weather system builds over the continental divide as BNSF's eastbound Provo, Utah to Denver, Colorado trackage rights manifest rounds the curve descending the 2-percent grade at Crescent, Colora... (more)

The snow-capped Continental Divide provides an excellent backdrop as BNSF's eastbound Provo, Utah to Denver, Colorado manifest rounds the curve at Crescent, Colorado with 98 cars on February 13, 2... (more)

Union Pacific’s EMD DDA40X “Centennial” No. 6936 powers a westbound engineering special at Crescent, Colorado, on October 4, 2001.

A summer edition of the Rio Grande Ski Train climbs the two-percent grade in the “Tunnel District” between Tunnels 16 and 17 in South Draw east of Crescent, Colorado, on June 23, 2001.

Amtrak’s westbound California Zephyr cruises through the snow at Crescent, Colorado, on December 22, 2006.

Burlington Northern Santa Fe MDENSTO (Denver to Stockton manifest) freight pounds out of Tunnel 18 just east of Crescent, Colorado, on May 23, 2001.

It's a gorgeous morning in Colorado's High Country as Amtrak's westbound California Zephyr rounds the curve before entering Tunnel 19 near Crescent, Colorado on September 20, 2015.