An eastbound Union Pacific coal train eases down the two-percent grade at Coal Creek Canyon between Plainview and Clay, Colorado, on a snowy January 5, 2005. the head end is passing mile 22.6, whi... (more)

After Union Pacific merged Southern Pacific, it continued to operate a Z train between Denver and Salt Lake City over the Moffat Line for several years before eventually moving it to the Overland ... (more)

A BNSF Denver to Stockton manifest freight, powered by a trio of GE C44-9Ws, works through the curves west of Clay Colorado, while climbing Union Pacific’s Moffat Tunnel Subdivision grade up the... (more)

On the bright spring day of April 28, 2002, an eastbound Union Pacific coal train descends a two-percent grade off the front range mountains of Colorado. The head end is just about completed round... (more)

My wife Katie, Riley the Beagle, along with Miniature Pinscher brother Kevin, intently watch the westbound Rio Grande Ski Train climbing through Big 10 Curve between Rocky and Clay Colorado, on Ju... (more)

BNSF’s Denver to Provo manifest freight slogs through a springtime snowstorm approaching Blue Mountain Drive grade crossing west of Clay, Colorado, on March 29, 2007.

A Union Pacific coal empty works westbound through Clay, Colorado, on the stormy afternoon of June 2, 2007. Big 10 Curve and downtown Denver can be seen above the pair of GE AC4400CW locomotives l... (more)

Union Pacific’s Denver to Salt Lake City manifest freight MNYRO climbs through a snowy Big 10 Curve between Rocky and Clay, Colorado, on February 2, 2014. Four GE AC4400CWs on the point of the f... (more)

A trio of Union Pacific GE AC4400CWs power a westbound UP coal empty upgrade past the east switch of Clay siding while climbing the two-percent grade around the Big 10 Curve on Colorado’s Moffat... (more)

Heading west on the old Rio Grande Moffat Tunnel main line, a Burlington Northern Santa Fe manifest freight, led by Santa Fe GE C40-8W No. 846, passes over the east switch of Clay siding climbing ... (more)

Moffat Sand A unit sand train climbs the Big 10 on the Moffat Road. The sand is headed for the oil and gas fields of Western Colorado and Central Utah. The vast basin between the Main Ran... (more)

Blue Looper on the Moffat
Burlington Northern Santa Fe GE C44-9W No. 712 leads an eastbound coal train at Coal Creek Canyon just west of Clay, Colorado, on May 24, 2000. Blue brake shoe... (more)

Santa Fe GE C40-8W No. 846 leads a westbound Burlington Northern Santa Fe manifest freight past the east switch of Clay siding climbing through Colorado’s Big 10 Curve on the afternoon of May 28... (more)

Private car “Kansas” carries the markers of the westbound Rio Grande Ski Train through a spring blizzard west of Clay, Colorado, on March 29, 2007.

In a early springtime snowstorm, the Rio Grande Ski Train curves west out of Clay, Colorado, on March 29, 2007.