David Moffat's Denver, Northwestern & Pacific (and later the Denver & Salt Lake) was posed with a seemingly huge problem in their construction of a line due west of Denver - how to cross the Continental Divide. At this point in the Rockies, all usable passes over the Divide are above the 11,000-foot level (making them prone to severe winter weather) and tend to have very challenging approaches, requiring stiff grades. The obvious answer would be to tunnel beneath the backbone of the Rockies at this point, but any tunnel of sufficient length would have required funding and time that the road did not have. Instead of constructing what was known as the Main Range Tunnel (a proposed 2.6-mile version of the Moffat Tunnel), Moffat chose to push over Rollins / Corona Pass with a temporary mainline that would get his road moving west of the Divide, with the intent to finish the Main Range tunnel within a few short years. The line reached the apex at Corona in late 1904, and much against the original plans would continue to serve as the mainline for over two decades.
Finally, on February 26, 1928, the first official train went below the Divide at a little over 9200 feet of elevation, rather than over the hill. An alternate, better Main Range tunnel than the one originally planned had been completed with the with the assistance of the state of Colorado. Christened the Moffat Tunnel, this 6.21-mile bore was built honoring the man who would never live to see it. It eliminated the long (in some accounts, as much as 12 hour) climb up the four percent grades of Rollins, as well as the ever present threat of natural disasters such as snow closures, and turned the D&SL into what would eventually be a vital part of the Rio Grande system.
Aside from a few days in 1929 when there was a minor collapse in the Moffat Tunnel, the Rollins Pass route was never to be used again. On 14-May-1935, the ICC granted approval for abandonment, and by October of 1936 the scrapping was complete. At that point, what remained of the roadbed and snowsheds was turned over to the Federal Government via the US Forest Service. It eventually became a road (excluding certain parts, such as collapsed tunnels 31 and 33), and was passable between Rollins and Winter Park until the collapse of Needle's Eye tunnel in the early 1990s. Since then, the road is permanently sealed off on the east side about a mile below the tunnel.
As many of you know, I have a fascination with abandoned railroad right of ways. I'm not exactly sure why, but one that I've been especially curious about since I was much younger is the Rollins Pass route. I thought some of you might appreciate a look at this critical but long lost piece of Colorado railroad history that you might not otherwise get unless you're here with a truck between June and September, when things are easily passable up at the top. The photos aren't particularly shocking or beautiful, just documentary. This trip report reflects the condition of things between where the routes diverge near East Portal to the east side of Needle's Eye Tunnel as they were in July of 2002. Hopefully you'll enjoy it - it's a bit different than the normal around here. Also, I'm planning to get to the west side of the pass sometime this summer, so there's a second half to this coming at some point.
For those looking for more reading, I might suggest The Moffat Road, published in 1962 by Edward Bollinger and Frederick Bauer, or P.R. "Bob" Griswold's Denver, Northwestern & Pacific / Denver & Salt Lake set of books, printed more recently (mid-1990s) by the Rocky Mountain Railroad Club. Both of these cover the line in-depth, with the history behind the decisions as well as a great number of photographs and drawings.