Electric fence kept insulated from the earth and from any materials that will conduct electricity and ignite or short out the fence. Fencing must therefore avoid vegetation, and cannot be attached directly to wood or metal posts. Typically, wooden or metal posts are driven into the ground and plastic or porcelain insulators are attached to them, or plastic posts are used. The conducting material is then attached to the posts. Electrified palisade fences are usually made from painted mild steel, galvanized steel, stainless steel or aluminium. Typically the fences are . The palisade fence is mechanically stronger than a typical steel cable
Battle of Alesia feed the troops. This reduced the number of troops at the Roman works. The Gauls made sorties with large forces to attack the works. Therefore, Caesar added further structures to the works to make them defensible by the reduced number of troops. Cut tree trunks were sharpened to create stakes. They were fastened at the bottom and sunk into a five "pedes" deep trench (1.5 m, 4.9 ft) with the boughs protruding from the ground. They were tied in rows of five so that they could not be pulled up without being impaled by the sharp stakes. Pits three "pedes"