I’ve been slowly working on a corner tunnel with scratch built portals. With an inclined outer loop I had to over size the height allowing a tall enough pass through. It makes for an unusual looking piece. I did the best I could to make it look like a tall concrete retaining wall. I’m sure it will look fine when I add trees and greenery. I originally wanted a base for a mountain, now I’m thinking on a stand alone industrial scene of some kind with lighting.
Gene