There were a number of dykes of medieval date existing in the North of England which may represent a defence against Scottish raids and/or mark out boundaries. As with all fortification such defences can only be of military effectiveness if garrisoned with a force capable of responding to attackers, when they can have a role in delaying an attacking force, particularly one loaded down with booty and livestock. Otherwise such boundary markers must function mainly symbolically.
There were a number of trench lines along the East and South coasts forming late medieval coastal defences.