Union Pacific’s Denver to Phippsburg freight rumbles through Rocky, Colorado, on the afternoon of October 23, 2011. Three levels of track can be seen here, and the freight will negotiate them al... (more)

UP 8455 (SD70ACe) assists a BNSF Grinstein MAC in shoving a BNSF freight through Rocky, Colorado in heavy fog and light snow.

BNSF 6948 (ES44C4) leads a freight in dense fog and snow through Rocky, Colorado as it gets ready to climb the Moffat Tunnel Sub into the foothills along the front range.

Amtrak engine 69 leads the California Zephyr through Little Ten Curve and will soon enter Big Ten Curve as it gains elevation climbing into the foothills of the Colorado Rocky Mountains.

BNSF 7016 (ES44C4) pulls a freight through Rocky, Colorado.

UP 6686 (AC4400CW) leads a freight through Rocky, Colorado.

After leading a freight down the Moffat Tunnel Sub, through Coal Creek Canyon, around Blue Mountain and through Big and Little 10 Curves, BNSF 7016 (ES44C4) gets framed from a duck blind at Rocky,... (more)

UP 3027 (SD70AH) leads a long line of UP motors through Little Ten Curve and will soon pass the Rocky Siding on the way to Denver, Colorado.

Union Pacific 8794 (SD70ACe) leads a train of hoppers through the Rocky Siding on its way to the UP's North Yard in Denver.UP 8794 SD70ACe.

To help trains manage the drop in grade from Coal Creek Canyon to Rocky, Colorado, there was constructed a series of sweeping curves known as Big Ten and Little Ten curves that help with the trans... (more)

With the Boulder Flatirons in the background, the California Zephyr rounds Little Ten Curve and will soon transition through the Big Ten Curve as it climbs the foothills towards the Colorado Rocky... (more)

BNSF 6524 (ES44C4) has just led an oil can train through Big Ten Curve and gets ready to split the signals at Rocky, Colorado.

Amtrak 73 (P42DC) leads the California Zephyr through Rocky on its way into the Colorado Rocky Mountains. The windmills in the background are at the National Center for Atmospheric Research (NCA... (more)

An eastbound Union Pacific coal train drops downgrade into Rocky, Colorado, while heading east on the former Rio Grande Moffat Tunnel route on April 13, 2002.

Union Pacific was testing Electro-Motive Diesel’s SD70ACes on the Moffat Tunnel Subdivision west of Denver, Colorado, on August 26, 2013. UP’s mobile laboratory car No. UPP 210 is bracketed by... (more)