Trying to find a better 'Osgiliath look' with the bases of Minas Tirith Warriors, I bought some plasticard designed as brickwork for railway modellers, from the Cheltenham Model Shop.
The size discs required for the tops of bases is a little less that the diameter of a pound coin.
The card glues with plastic glue (I suppose it would, being plastic) and then the troops have to parade without their slot.
I cut them off with cutters and then cut and filed the bottom of their boots to glue them on the tiled roads of Osgiliath.
The surface of the card seems ok with paint as long as it's not thinned down too much.
A coat of Codex and a wash with Badab with a drybrush of Fortress Grey after glueing on some rubble from the ruins.
Plus a few weeds popping up, here and there.
Let the Orcs do the weeding when they arrive!