Looking east along Cawfields Crags.The Wall goes over the tops of all the hills in shot,but does not descend to the modern farmhouse.NB:Just below the farmhouse,upper right,can be seen the vallum.Purpose,unclear.It runs the full length of Hadrian's Wall,behind the wall at varying distances.It's probable that it simply demarked the Military Zone.Remember,that for all their brilliance and achievements,such as Hadrian's Wall,they hadn't invented mass production of wire,and so were incapable of making even a simple fence,such as is in shot.