Immediately beyond the end of the Wall visible in the middle of the shot,is a drop of about 50feet,due to quarrying.
When historians talk of stone robbing this is a good example of what they mean.This is all that's left of a once proud structure,in this location.It stood 8 ft.wide and 15 ft.tall to the walkway with a 6 ft.parapet also in stone.All the exterior stonework was "dressed" stone.Now all that remains is this dribble of rubble interior.see http://www.pbase.com/taggart51/image/164507772