Walls are very easy to make, and create HardCover that really adds
an extra touch to the game.My walls are made from foamcore, 3-4cm high, at least high enough to completely cover a miniature, and 5 or more cm long. They are based on another piece of foamcore, to give it some stability. I cut a 45° angle on top of them, to glue some shingles on. Two or three small rectangles of card are glued to the walls to create the image of being constructed out of real stones. The walls are then covered with ready-made filler, without covering the small "stones".
The base is covered with WhiteGlue and then with birdsand. The walls are covered with ready-made filler, which gives some texture and takes the look of being "only" a cardbuilding. I then undercoated with ChaosBlack spraypaint, then drybrushing everything, including the base, with CodexGray. The base was then drybrushed with a light brown, highlights with BubonicBrown. The shingles were painted individually with Red.
Another material that I used in the past is 4cmx1cm wood from DIY-Shops, which you can cut into your desired lenghts. I based this using the method described above. This is actually cheaper than using foamcard, but with foamcard it is easier to make doorways, ruined sections and so on. But if you just need several "normal" wall-sections, it is an option.
