Another popular Train Simulator with the notable highlight of being freeware! Also note the new OpenBVE version with many new features - well worth a look!
Have you seen these screeshots of this line (available here: http://www.railsimroutes.co.uk/ , then project, then clic on the line and screenshots)
It looks wonderfull! I don't know if it is real photos or screenshots from the sim. The track, the trees, all look so real. I'm really stunned by that!!