Still have not started layout yet due to health problems and helping granddaughter but I decided I would not build any large scenery that is not easy to take off if I should take the layout down. I built a corner mountain/hill to see how it would look and this is what I came up with. The bottom is flat so attaching it with a few spots of hot glue will be no problem. The backside is a 90 degree just like the plywood would be and the front is a semicircle. Under brush along the edges will hide the cardboard. Same construction as before, cardboard, dryer sheets, hot glue, some plaster molds, plaster and washes.