The Moffat Tunnel line through the Continental Divide west of Denver, Colorado, is one of the most spectacular pieces of mountain railroading to be found anywhere in the world. Superbly maintained 136 lb. welded rail laid on 2 percent grades, under a backdrop of the snow covered Continental Divide, 50 tunnels, and deep river gorges.

In the 1860s, Denver was a brand new town, formed around the first gold discoveries in the area and well on her way to becoming the financial and economic center of much of the Rocky Mountain region. Yet 40 years later, Denver was still without the direct services of a transcontinental railroad she so desperately needed for continued growth. All Denver had available was a connection to the Union Pacific's transcontinental route through southern Wyoming, 100 miles to the north; or the Rio Grande's line over Tennessee Pass over 100 miles southwest of Denver, effectively leaving Denver subject to exorbitant freight rates of these two railroads.

But the rocky fortress west of Denver seemed impregnable to railroad builders in the latter half of the 19th century. Even the mighty Union Pacific, with all their backing from the U.S. government, had decided they could not build through them, nor could any other railroad promoters. But David Halliday Moffat, a multi-millionaire from successes in mining, banking, and railroading, knew he could. He formed the Denver, Northwestern & Pacific Railway and started construction in April, 1903, planning to conquer the high Continental Divide with a tunnel.

The "Moffat" faced its first challenge a mere 15 or so rail miles from Denver, the almost solid ridge of high Rocky mountains running north to south as far as the eye can see: the "Front Range." The grade needed to climb directly into the foot hills would have been over 2.5 percent up to the mouth of Coal Creek Canyon, where a 6,000 foot tunnel and electrified line (to avoid smoke problems in the tunnel) was planned to carry the rails through the first tall escarpment of the Front Range into the more spacious South Boulder Park below the Continental Divide.

Instead the tracks were lengthened to lessen the grade to 2 percent, and also eliminate the single long tunnel in Coal Creek in favor of multiple shorter tunnels. The result, the "Big Ten," a set of twisting, climbing curves so named because each does not exceed 10 degrees - takes trains in every direction on the compass to reach the mouth of Coal Creek Canyon.

Rio Grande Ski Train at Prospect Junction (with BNSF), March 1983.

Ski Train at Utah Junction, where Moffat rails headed west.


Leaving Leyden siding in Arvada.

Rocky siding, at the base of the Big Ten.

Looking east from Clay siding, the mid-train helper set of a loaded coal train passes the west switch of
Rocky siding while the head end nears East Rocky about 330 feet below Clay. The line off to the left is
the spur to the former Rocky Flats nuclear weapons plant.

The lead power of an eastbound coal load drops down through the "Big Ten" curves while the rear of the train
is still passing the east switch of Clay siding, some 125 feet higher. It is easy to see how, in the days of steam, a brakeman
could drop from his westbound train and run up the hill to throw the Clay switch before the front of the train arrived.

Blue Mountain Road crossing in Coal Creek Canyon.
Tunnel 1 in the "Tunnel District" is just out of the top right edge of each photo.

HY 72 bridge in Coal Creek Canyon, below Tunnel 1.

Climbing towards Tunnel 1.

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Thirty VS One      No More Hill Hell      Canyonlands and Horseshoes
Through the Rockies in Grande Style      Union Pacific on the Moffat

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