The California Zephyr heads runs through Plainview, Colorado, passing the construction vehicles that are prepping the once-pristine mountain for new homes.

The California Zephyr heads towards Tunnel #1 at Plainview, Colorado after having run through Coal Creek Canyon.

The California Zephyr exits Tunnel 1 at Plainview, Colorado as it starts the climb through the Colorado Rocky Mountains.

With the Boulder Flatirons in the background, BNSF 8384 (ES44C4) leads an oil can train through Plainview, Colorado.

In what could be a scene from the 1990's with a Heritage IV Genesis pulling the California Zephyr, Amtrak engine 184 pokes out of Tunnel #1 at Plainview, Colorado.

The California Zephyr makes the climb to Tunnel #1, along a stretch of track that has 3.4% grade, the steepest grade on the Moffat Tunnel District.

A passenger standing in the back window gives a friendly wave as Amtrak heritage engine 184 (P42DC) leads the California Zephyr through Plainview, Colorado on the Moffat Tunnel Sub.

UP 5131 (SD70M) leads the Rocky Mountaineer passenger train up the Moffat Tunnel Sub towards Tunnel 1 at Plainview, Colorado.

The California Zephyr is emerging from Tunnel 1 at Plainview, Colorado.

Amtrak heritage engine 184 (P42DC) leads the California Zephyr out of Tunnel 1 at Plainview, Colorado. A friendly wave and a horn toot from Engineer Gary was most appreciated!

Amtrak engine 28 leads the California Zephyr through Plainview, Colorado and within the hour will be stopping in Denver's Union Station.

The rolling hills of Coal Creek Canyon and Plainview, Colorado provide a scenic backdrop to heritage engine 184 as it runs the California Zephyr on the Moffat Tunnel Sub.

Heavy snow has coated the Boulder Flatirons rock formation as the California Zephyr makes the trek into the Moffat Tunnel Sub.

Amtrak engine 138 (P42DC) leads the California Zephyr through the sweeping curve at Plainview, Colorado.

From atop tunnel 1 on UP’s Moffat Tunnel Subdivision, we see the Rocky Mountaineer snaking around the bend led by a pair of UP SD70Ms as the begin their journey west through the Rockies.