UP 7459 (ES44AC) sits with other Union Pacific power in the large North Yard in Denver, Colorado.

Two Denver RTD commuter trains pass each other at Denver International Airport.

PRLX 4102 (SD40-2) assembles a stack train at the intermodal facility in Hudson, Colorado.

BNSF 9275 (SD70ACe) leads a loaded coal train past a pond at West Tonville, Colorado.

The California Zephyr casts a reflection at Barr Lake as it heads towards Denver, Colorado on the Brush Sub.

Fresh snow overnight has frosted the trees in Coal Creek Canyon as the California Zephyr heads into the Rocky Mountains.

A pair of new Phase VII 42's lead the California Zephyr through Coal Creek Canyon, Colorado.

BNSF 5656 (AC4400CW) leads a loaded coal train through Hudson, Colorado.

BNSF 5656 (AC4400CW) leads a loaded coal train through Keenesburg, Colorado.

UP 1507 GP40M heads in from the yard after a day or sorting cars in the Union Pacific's North Yard.

RTD commuter train #4012 (Hyundai Eagle P3) heads towards Denver International Airport on the A-Line.

BNSF 9072 (SD70ACe) waits at Pinecliffe, Colorado for the westbound California Zephyr to pass.

BNSF 6039 (ES44AC) shoves a coal train through Spruce, Colorado as it heads south on the Joint Line.

PRLX 4102 crosses the road with a cut of cars from the BNSF intermodal facility in Hudson, Colorado.

Two gloss black PRLX leased SD40-2's work the intermodal facility in Hudson, Colorado.