
Tunnels & Mountains
Tip # 1 - Make a small coal mine
Take a N-Gauge Tunnel and cut it to fit against you HO scale layout's mountains
or a painted mountain backdrop. Use landscaping materials to hide the joint.
Use N scale track to simulate the mine track. Put a sign over the entrance,
and pile coal randomly around the mine. Next place miners and an ore car
to complete the scene.

When you pour your plaster for the outside entrance area, just before it sets up, take an exacto knife or other sharp object and pick away at the plaster so it appears chipped and rough. Leave this one tunnel entrance rough to look like the workers haven't finished added the wood or concrete face to the tunnel. Basically a tunnel in process.

Another way to add smoke is to use smoke. Take a candle and light it. Hold the flame under the tunnel entrance, the farther away you can hold it, the better, the soot will rise and char the entrance for real.

Put the stones and other material near the entrance to the tunnel, but not blocking the track.
Place men with shovels, a truck, road barriers and other details around the rock slide as if it were being cleaned up.
Another idea is to run a set of tracks into a tunnel opening and then pile boulders and rocks etc. in the entrance to simulate a cave in. Obviously you don't want to do this on a piece of track that you are running trains on, just make a fake siding some place.

