These would ideally be suited for the foamboard that has the black foam core. I was going to make one but didn't get round to it, sorry. However, that black foam would make these easily playable from the off, without looking too much like a quickly knocked up bit of terrain.
To access the full STC please point your Cogitators here, be fair warned it is 10MB in size [I make no apologies for this, I could probably render it as a .jpg or spend hours trying to reduce the file size, I tweaked it a little bit and got it down so hopefully it's less of an issue now.]:
Meanwhile all the other Print & Play and standard terrain templates are available here: