Thank you, Dave Ripp, Dave arlander, Mike, Bob, Jay!
Dave Ripp, One for road into the tunnel. The roads into tunnels that are common in my area on the B&LE are made of cut stone sort of like Pennsy style and are only one lane wide. Most have the road coming from one direction at an angle to the tunnel so you can't see oncoming traffic and have to blow your horn before going through. They were certainly well built.
Dave darlander, One for the road winding down into the valley. I think that option makes the most sense in the real world.
Mike, One for The Bridge to Nowhere, a name of infamy for the now Fort Duquesne Bridge that is between PNC Park and Heinz Field. 
Bob, Two for dead end and Two for the tunnel. Yours is an excellent example! Very well done. Good point about Richie's workers' wages.
Jay, the mirror is a good idea. I have seen it done often, but have never done it myself.
Thank you everyone for the ideas. I do like the tunnel. I'm going to ponder it for a while and also see if there are any more suggestions.
