There is very little indeed of Procolitia to be seen on the surface. The famous well of the water-goddess, Coventina, is merely a patch of rushes railed round, and too wet even to be examined. It is just possible to make out the walls and gateways of the fort under the grass. The great Wall joined on to the north wall of the fort. The Vallum curves round to the south to avoid it.
The first cohort of the Batavians was stationed at Procolitia; and the Tungrians were stationed at the next fort, Borcovicium. This is significant, because Tacitus mentions that Batavians and Tungrians fought side by side in Agricola's army when he won the battle of Mons Graupius. So it seems that they first came to Britain under Vespasian.
After we have passed the farm-house of Carraw, built by the monks of Hexham for a summer residence, Sewingshields comes into full view, nestling in trees, exactly over the top of the next hill in the road. The land has now become still more bleak and barren; there are no longer fresh green pastures, but brownish sheep-moors, dotted with tufts of rushes and coarse grass. Presently I saw something dark sticking up in the long grass by the side of the road. I was meeting the wind, so I got quite close before it moved. It was the two dark ears of a hare which sped like lightning, when it saw me, under a five-barred gate on the right, and so across the moor, till it vanished, as a speck, over the horizon.
And now at last the Wall leaves Wade's Road, so I climbed over the stone fence which bounds the road to walk on its grassy mound. It diverges more and more from the road, and makes straight for where the crags begin at Sewingshields.
It soon brought me to a very interesting mile-castle which has been excavated. The northern gateway is the first good specimen of a mile-castle gateway that we have come to. It is fenced round to protect it from animals. I clambered over the stone dyke and down into the Wall-ditch, to gaze up at the massive masonry, which looks much more imposing seen from the north. Nine courses of stones are in place on the western side of this gateway.
There were now two stone dykes between me and Wade's Road. The Wall-ditch continued to be very deep and striking. Flags and water-reeds covered its bottom, and great boulders lay strewn about.
At a fir-plantation the Vallum crosses Wade's Road, and from this point onwards it runs along in the low land while the Wall clings to the heights.
On this May day the brown moorland to the north of the Wall was thickly sprinkled with cotton-grass, its downy white heads giving a silvery sheen to an otherwise dull expanse. "Moss-troopers," the children call them, a white army invading from the north! Or, as a farmer's wife put it to me: "They bits o' flooff would mak' ye think we'd had a shower o' snaw."
And so I came to Sewingshields, where the most fascinating part of the walk begins.