A while ago I mentioned how useful two things I'd found in my local pound store would be for making roads. The first was black sandpaper and the second was vinyl tiling. Inevitably, I combined the two, and made a large quantity of double-sided, verge-less roads for 6/15mm. There's some diluted PVA on the "tarmac" side to ensure that I don't end up with black grit everywhere, and a light spray of grey to take the harshness off the black. On the other side, I applied some cheap varnish, then some weathering powders, then a matte varnish spray to give the stone roadways a bit of character. Here's a few shots of planning and the results.