I was looking for this route...

I believe it's part of the Denver and Rio Grande Railroad. I don't know this area or route but I would love to run a train on it if anybody made it.:)
That web page described several different railroads, both narrow and standard gauge. The picture in the direct link is the Cumbres and Toltec Scenic Railroad (I think), a DEM is available on the DLS by fishlipsatwork, or search the forum and you will find screenshots of an unfinished version of this route.
Other routes mentioned and illustrated in the article are the Durango and Silverton Railroad (DEM available on the DLS and at least 6 different uncompleted versions being worked on by various people - including me!), and the Techappi loop - this available from TrainzProRoutes.

Dave Bird
I was more specifically looking for the area first shown as, Marshall Pass. I thought that would be a pretty area to travel.