Once upon a time, the railroad industry was one of the largest work forces in Colorado. From the Union Pacific to the Rock Island and more, nearly every corner of the state was impacted by the fast-paced business of moving goods and materials back and forth. Needless to say, the Denver area was no exception and welcomed many trains to the area throughout the years (and even today). In order to accommodate these large locomotives, tunnels — like the Moffat Tunnel near Denver — were a necessity and took thousands of hours (and even more manpower) to complete.

Flickr/Jeffrey Beall

Flickr/Spencer Blake

Flickr/Sean Gillies

Originally developed in 1902 by Denver, Northwestern and Pacific industrialist David Moffat, the Moffat Tunnel was built as a means to provide Denver with a railroad connection to western Colorado via the Continental Divide. Even though it was first proposed at the beginning of the 1900s, it took nearly 30 years to complete, as Southern Colorado legislatures feared that Denver would have a one-up in terms of commerce if the route was built. Once tunnel construction was in full force, there were still obstacles to overcome, including an instance when workers struck a patch of bad rock near the west end of the tunnel, which delayed construction and increased production costs (the tunnel was originally projected to cost $6.62 million, but the final price tag turned out to be a whopping $23,972,843!). The historic tunnel is still open today and is primarily used as a way for the Union Pacific Railroad to transport coal and freight.

Flickr/Jeffrey Beall

Flickr/Spencer Blake

Flickr/Sean Gillies

Ready to take a look at the production of this important tunnel? Check out these photos from our friends at History Colorado:

1.) “Stereograph dry plate glass negative depicting three unidentified men, likely employed to work on construction of the East Portal of the Moffat Tunnel in Gilpin County, Colorado, at the site of the tunnel construction during the winter of circa 1922-1923. They are standing in front of a steam locomotive.”

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2.) “The left-hand image depicts Frederick Douglas Hall (1866-1938), an African-American man who lived in Denver, Colorado and was employed as an engineer and brake man for the Denver and Rio Grande Western Railroad Company. He stands in front of some of the buildings located at the site and holds a pocket watch. The right-hand image depicts three unidentified men who were likely employed to work on construction of the East Portal.”

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3.) “Two men in front of the East Portal of the Moffat Tunnel.”

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4.) “Buildings at the East Portal of the Moffat Tunnel: the buildings housed the workers and foremen who worked to build the tunnel.”

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5.) More buildings along the East Portal that housed workers during the winter of 1922.

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6.) “Modern” construction equipment at the site of the (then) future tunnel.

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7.) “Photo of the interior of the newly completed Moffat Tunnel.” (1927)

Wikimedia Commons

8.) Engineers standing in front of the finished tunnel, 1944.

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For even more nostalgic goodness, check out these 11 Vintage Photos Of Denver’s Streets That Will Take You Back In Time!

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Wikimedia Commons

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