We started to work on structural support for Scenery on the layout. Styrofoam is an excellent material since it is lightweight and can be formed easily. A source of white Styrofoam pieces is packing in boxes for different goods and appliances we buy. A lot of these pieces can be used as is to form the structure for terrain. Cutting these does make a mess with the charged particles that result.
Here is some work we have done at one end of the layout where there is a tunnel portal .
on the back side of the upper level bridge crossing the duckunder
on the left side of the portal
;and the right side. Here I used some pink foam board which makes a wall from the upper level to the lower level
And an overall view. All the Styrofoam has been glued with white clue to the wood table and to each other. When the Glue dries this will be a pretty rigid and lightweight structure to support the Woodland scenic plaster cloth to form the terrain.