Wire obstacle

In the military science of fortification, wire obstacles are defensive obstacles made from barbed wire, barbed tape or concertina wire. They are designed to disrupt, delay and generally slow down an attacking enemy. During the time that the attackers are slowed down by the wire obstacle (or possibly deliberately channelled into killing zones) they are easy to target with machinegun and artillery fire. Depending on the requirements and available resources, wire obstacles may range from a simple barbed wire fence in front of a defensive position, to elaborate patterns of fences, concertinas, "dragon's teeth" and minefields hundreds of metres thick.