Before arriving at the final trackplan I built a mockup of the proposed layout. I recently (re)discovered the mockup so here is a picture of it showing the curved trestles across Cascade Slough, the location of the hills behind South Jackson and the routes taken by the twice-around mainline.

I printed and glued the track plan to some 1/4" FoamCore. Then I cookie-cuttered it and adjusted the elevations of the differnt track locations. Finally I added a bit of crude scenery with clay.

Here's a link to one of the few "overall" pictures of the 4x8 BC&SJ layout.