Jerry: Do you have any definitive info on the semi-abortive railroad partially completed from Crested Butte to the Yule marble mines above the town of Marble. For years I had a treasured cabin in the Pittsburg townsite below Yule Pass. I used to look out of my cabin and see the mile or so of grade completed on the side of Yule Pass before the idea was given up. I spent a great deal of time tramping around the ridge on the east side of the Slate River valley, but never did find any evidence of any grading having been done down that low. I had sort of assumed that the projected railroad would have stayed on the side of the ridge while descending, and eventually connecting with the end of the D&RGW's Anthracite branch.
Another possibility is that the line was projected to cross over the low saddle between the Slate River and Washington Gulches. What bears this out in my mind is that the road climbing north out of Pittsburg is fairly steep and the grade varies until the turnoff to Washington Gulch. From there to the top of Paradise Divide the road grade is nice and even and slightly less steep - more in line with a railroad grade. A railroad would have had a fairly easy time of it in Washington Gulch down to the Crested Butte townsite, except for the very top end of Washington Gulch which might have demanded some creative engineering.
Do you have any conjectures?
CJ