The hardest part of all this is making it believable, because as the river curves to the right, it has to come to an end before it reaches the hidden track in the tunnel, and the road has to end as well, off to the left, into the backdrop. I'll be using the model of a cast concrete road bridge (from Walthers) and lots of trees as view blocks, so the river's end won't be seen from normal viewing angles. Final scenic elements, like vehicles on the road and bridge, will help, too. If your eyes can't see it, your brain is less likely to raise the question!
The hilltop over the tunnel entrance will be removable - this is one of the few hidden trackage areas I can't access from underneath the benchwork. Beyond that tunnel portal and deck girder bridge, I'm just starting to rough in the foam - this section should be a lot easier.
Yeah, it's a mess working with the foam!