Taking this assessment from the trees on the left of shot;the line of grassy mounds just infront of the trees is the remains of The Wall.The Antonine Wall was constructed of essentially turves,stacked one on top of another.The turves were of a uniformed size,being 18"x18"x6".A base layer of cobbles would be laid,and in some cases,a revetting wall up the back of the structure.The turves would then be stacked to a height of 12ft,with a wooden palisade and wooden walkway on top.The front of the Wall would be inlaid with spikes of wood.However,one of the drawbacks to such a structure was that,over time,it would slump,and need to be replaced.The Wall ditch,dug infront of the wall,can clearly be seen in shot.
see http://www.google.co.uk/imgres?imgurl=http://www.undiscoveredscotland.co.uk/falkirk/roughcastle/images/roughcastle-450.jpg&imgrefurl=http://www.undiscoveredscotland.co.uk/falkirk/roughcastle/&h=338&w=450&sz=57&tbnid=acnFlLrR_bfqOM:&tbnh=107&tbnw=142&zoom=1&usg=__8TS_en4F4UhMgAGIdOdtyoRzy2g=&docid=istNh933KmAx2M&sa=X&ei=vpIhUrCrIOq00wXvv4C4DQ&ved=0CFsQ9QEwAQ&dur=10227