I'm looking for some ideas on tunnels... so if anyone with their own, or pics/links to others, would be appreciated. I'd prefer to have scratchbuilt, and not to have the store bought kind, but I'll take anything at the moment. Is there a refrence link (with pics)?
We made the Rock Springs ones from wood, painted to represent concrete. This one has a short rock shed at the entrance... This is the "plain" variety. They were styled after looking at tunnels on various western railroads. Scale is HO, but I guess these would work in any scale.
IMHO, I don't recommend tunnels. It is too hard to fix derailments and clean the track. That being said, I would be sure that access to your tunnels is generous. There should be some way to lift the mountain off the track or get to the track from the asile. It is like duckunders in that they are not recommended but sometimes necessary or unavoidable. I think tunnels are much more preferable than duckunders.
Definitely leave some way to see inside the tunnel. And to get your full sized hand inside for cleaning rails, or for recovering "items." OK. Not "items." The inevitable derailed train. Boxcab E50