Heavy snow is falling on the BNSF engine servicing facility in Denver, Colorado.

BNSF 2530 (GP39-3) runs to the BNSF yard in Longmont, Colorado.

BNSF 6717 (ES44DC) brings the DenLau freight train into Denver, Colorado.

UP 845 (GP38-2) sits in the North Yard along with a Southern Pacific patched unit.

UP 1507 (GP40M) brings a freight into the BNSF yard in downtown Denver, Colorado.

UP 9050 (SD70AH) shoves an oil can train through Pinecliffe on the Moffat Tunnel Sub.

UP 6608 (ES44AC) leads a freight south on the Greeley Sub through Brighton, Colorado.

UP 9050 (SD70AH) runs along a shelf as it muscles an oil can train towards Rollinsville, Colorado on the Moffat Tunnel Sub.

UP 9003 (SD70AH) leads a long oil can train down the valley into Tolland, Colorado after exiting the Moffat Tunnel east portal.

BNSF 6004 (ES44AC) leads the BNSF Provo train through tunnels 4, 3 and 2 as it heads to Denver, Colorado on the Moffat Tunnel Sub.

Amtrak engine #19 (P42DC) leads the California Zephyr through Keenesburg, Colorado at sunrise on the Brush Sub.

Two fresh-looking OmniTRAX GP40-2LW's (former Canadian National motors) hold the track at the large industrial facility in Windsor, Colorado.

Coors Critter #998 (SW1001) moves a cut of cars to the brewing facility in Golden, Colorado.

You can still find a working Grinstein in Denver, Colorado. BNSF 9709 (Executive SD70MAC) works the Beer Train that moves between the Coors Brewing plant in Golden, Colorado and the BNSF yard in ... (more)

With the majestic Boulder, Colorado Flatirons in the background, the California Zephyr runs through Little Ten Curve at Rocky as it begins the journey up the Moffat Tunnel Sub.