I want to have fortification but existing one are way too expensive.
Hence, I decided to scratch-build them with inexpensive material: extruded polystyrene foam.
Here is the prototype:
Wall are 12.5cm section. Gate could be removed from the gateway.
Foam is engraved with a milliput negative I've molded from a scratch-build wall.
This way I can produce wall very fast. I'm now ready to mass-produce walls, towers and gateways