The first problem - what to do with a lot of grey plywood. To someone used to modelling in garden scales it represents little more than the height of a single-storey building. Here it suddenly becomes many feet of vertical dimension. The solution, for the time being at least, was to turn most of it into sky. The ends could include rock faces once some portals were fitted to the track apertures. I experimented with bamboo for these, resisting the temptation to revert to my Chinese, or rather ex-pat British, supplier for some neat-looking grecian-style columns. Despite the discount offered, they wouldn't quite fit the style.