The California Zephyr #6 runs through an S curve cut in Crescent, Colorado as it heads into South Draw on the way to Denver.

Amtrak engine #18 (P42DC) runs past Barr Lake in Brighton, Colorado.

RMRX 8020 (GP40-3) leads the Rocky Mountaineer passenger train out of Coal Creek Canyon and towards Tunnel #1.

Hudson Terminal Railroad's Alco S1 works a cut of oil cans in the large yard in Hudson, Colorado.

BNSF 8761 (SD70ACe) waits for a westbound to pass before releasing from the siding in Pinecliffe, Colorado.

BNSF 6109 (ES44AC) runs south on the Joint Line, leaving the skyline of Denver behind.

The California Zephyr runs through the aspen trees in Tolland, Colorado as it heads west on the Moffat Tunnel Sub.

Canadian National #3321 (AC44C6M) runs south on the Joint Line as it leaves the city of Denver, Colorado behind.

BNSF 8537 (SD70ACe) leads a freight through Pinecliffe, Colorado as it heads to Denver on the Moffat Tunnel Sub.

BNSF 6329 (ES44AC) leads an oil train through Pinecliffe, Colorado.

Amtrak engine #76 leads the California Zephyr west towards Tolland, Colorado on the Moffat Tunnel Sub.

BNSF 9716 (SD70MAC) leads 'The Switch' back to Longmont, Colorado on the Front Range Sub.

BNSF 4251 (ES44C4) leads the Z Train through Roggen, Colorado on the Brush Sub.

BNSF 8125 (ES44C4) runs into the cut east of Akron, Colorado as it heads east on the Brush Sub.

BNSF 8593 (SD70ACe) notches up as it leads a train north on the Joint Line towards Fountain, Colorado.