ModelRailroadForums.com is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Online since 2002, it's one of the oldest and largest model railroad forums on the web. Whether you're a master model railroader or just getting started, you'll find something of interest here.
I used foam pieces for tunnel supports, crumpled up newspaper, taped down, for shape, then strong paper towels dipped in plaster paris to coat both sides, then lay it down and kinda smooth out. Easy, but messy. Hopefully I can make the back side so it will pull away for track access. That will be an experiment.