An off-road vehicle is often your best choice for exploring the sites of Colorado's extensive railroad history. It therefore follows that some members of the off-road vehicle groups would find some crossover interest. The folks at UTV Weekly put together a nice piece on Hancock Pass and the Alpine Tunnel, complete with photos.
The Alpine Tunnel was an endeavor by the Denver, South Park & Pacific (wikipedia), a narrow gauge railroad founded in 1872 with a small but hardy following among narrow-gauge railfans. In 1889, the DSP&P became the Denver, Leadville, & Gunnison (UP-controlled) and then in 1898, part of the Colorado & Southern system. The Alpine Tunnel was in use from 1881 to 1910, connecting Leadville and the Arkansas River Valley with Gunnison and the western slope.
Having visited the site a few years ago, I can tell you that the progress at the Alpine Tunnel historic district is noticeable, but slow. Hard, grueling work is complicated by the short summer--if you can call it that--along with the high altitude and lack of funding, things that conspired to prevent the original route from completion and continued operation. If you look at the photos, you'll see that even the memorials are not immune to the harsh conditions. Yet it is all worth a visit, if only to see the beauty of the state and embrace the history of men who bravely fought and died facing the worst conditions Colorado's Rocky Mountains could throw at them.
Further & Related