Never been to the Loop yet. Maybe some day. Here's another shot that would have been phenomenal to have a train. The Flatirons west of Denver at first light:
I think they were waiting for a good break in traffic to clean it all all up. Back in 2007 coal was strong.
San Luis & Rio Grande, La Veta Pass route, former D&RGW, between Mortimer and Sierra, CO; the grade here is 2.5%:
The old Denver & Rio Grande route just northwest of Redcliff on the Eagle River. The rails, under the snow, are below both highway bridges.
The Tennessee Pass route is one tailor made for vistas like that. I would love to explore it. Here's another La Veta Pass view. East Sierra Siding. 2.5%, just a couple of miles east of the above photo I posted. The catch here is the gated community that is developed here. There is no public road access from here to Occidental on the east side of La Veta Pass, more than 20 miles away. This make LVP a very remote, difficult to railfan, virtually unknown territory to anyone by train crews and those who ride excursions on SLRG.
The San Luis Valley is noted for potatoes, scoria, lumber and other commodities. Probably the Big Boy?