Along the Walls of Hadrian and Antonine

The Emperor Hadrian, who visited Britain in the year a.d. 122, left his mark upon this as upon the other provinces of his great Empire. The frontier-line which he wrought in northern England mapped the course of much of our early history and left us, incidentally, a monument which is one of the wonders of Europe. For, in spite of other views which have from time to time held the field from the sixth century almost to the present day, it is now known beyond doubt that the famous stone wall that straddled Britain from the Tyne to the Solway was the work of Hadrian and his staff. Controversy now rages only in regard to the exact relationship of this wall with certain associated structures of which something must be said in due course.

First, let us glance at the circumstances under which the wall came into being. Like most of the Roman frontier-system in Britain, it owed not a little to the far-sighted work of the famous Governor, Agricola, who between a.d. 77 and 84 completed the conquest of Wales and carried Roman rule to the extreme limits of its expansion in the North. Incidentally, Agricola built a military road, known as the Stanegate, across the island from Newcastle to Carlisle, and placed along it a series of forts at Corbridge and elsewhere. Some forty years later, in consequence probably of a formidable native revolt, additional forts were built along the same line, as at Throp and Haltwhistle Burn; but in or soon after the year 120 this rather haphazard development of the system was replaced by a new and more comprehensive scheme which was destined to culminate in the building of the famous wall itself.

In its original form, however, the new scheme included nothing so ambitious and costly as a continuous frontier-line of stone. A line of some kind was, it is true, now desirable for administrative purposes; a line which would define, for all to see, the exact point at which the pacified Roman territory and civil law came to an end and the potentially hostile "barbarian" territory and martial law began.

For this purpose the easiest type of construction was that to which many generations of field-warfare had trained and hardened the Roman armies-a construction of ditch and bank.

Accordingly from Newcastle, the site of the Roman crossing of the lower Tyne, to a point west of Burgh-by-Sands on the Solway, a ditch 30 feet wide, flanked on both sides by banks 6 feet high and 20 feet wide, was now drawn across the neck of England. At varying distances to the south of the stone wall this great earthwork, in spite of the ravages of time and the farmer, still deeply furrows the countryside.

The vallum, to give the earthwork its conventional name, is not in itself a work of defence. At several points it is dominated at short range by rising ground to the northward, or rendered unapproachable by marsh to the southward. It is merely the literal translation of a political boundary from the map. Nevertheless, it would have been useless without defence; and this was provided by a series of small forts which were laid out, contemporaneously with it, or, rather, slightly before it, since it often bends to avoid them-towards the hostile north. They lay from 2 to 8 miles apart and were from 2½ to 3 acres in extent, sufficient to hold a small cohort or battalion Of 500 men. Forts and vallum were completed within a year or two of a.d. 120. Such was the immediate forebear of Hadrian's Wall, and such, probably, was the frontier which the emperor himself found there in the year 122. If so, his visit was the signal for change and development. The process is doubtful in detail, but the main result is certain. Between 122 and 127 (the dates are indicated by inscriptions) the frontier-garrison was increased, several of the forts, notably Chesters (the Roman Cilurnum) and Birdoswald (Amboglanna), were enlarged, and from sea to sea-for 73 miles, from Wallsend (Segedu num) to Bowness-the forts were joined up by the famous stone wall, upwards of 12 feet in height and generally about 8 feet in thickness, with a ditch about 35 feet wide beyond its northern face.

At intervals of a mile the wall was pierced by gateways, which were covered by small forts or "mile-castles," each about 60 feet square and capable of housing a patrol of 100 men; whilst at distances of 500 or 600 yards between the forts and mile-castles were small towers, each about 13 feet square, for use as signal-stations and as staircases. The whole system was linked up by a military road which ran from fort to fort and threw out branches to the mile-castles and towers. Substantial remains of all these units still stand in many places, notably in the neighbourhood of Housesteads, which was the Roman Borcovicus.

Unlike the vallum, the wall was a military work. Its object was twofold; first, to provide a commanding sentry-walk from fort to fort, and secondly to control traffic and to provide a momentary obstacle to hostile raid or attack. Where its course crossed a river it assumed the form of a fortified bridge, dominated by terminal towers, and the remains of the wall-bridges at Chollerford and Willowford are amongst the most imposing examples of Roman masonry in the country. Ashore, it took full advantage of the tactical possibilities of the country which it traversed. Wherever possible, it climbs to the crest of hills and clings to the margin of precipices, always with the steeper side to Cheviot.

The process of its making had not been simple. Close behind its chosen site lay the vallum, which had to be pierced and bridged for the traffic of the builders. Scientific excavation carried out in recent years by Mr. Gerald Simpson has shown how this was done. At intervals of about 45 yards-as, indeed, the visitor can often see for himself to-day-the two banks of the vallum were breached; and the material thus available was used temporarily to form a causeway across the central ditch. Later, most of these causeways were removed and their material was distributed along the lip of the ditch to form the low marginal mound which is still visible at many points. This clearance indicates that, although supplemented for military purposes by the new stone wall, the vallum had its political significance.

More puzzling is another feature which is now being explored by Mr. Simpson. In the neighbourhood of the Roman fort at Birdoswald, between the vallum and the wall, is an intermediate defence, consisting of a large bank built of turves and fronted by a defensive ditch. This bank and ditch leave the line of the wall about a mile west of Birdoswald and actually pass under the fort which, in its present form, is therefore of subsequent date. But the fort is contemporary with the wall, and the turf bank must therefore represent either a preliminary experiment or a temporary safeguard during the evolution of the final scheme. The whole problem must at present be left to the archaeologists.

The building of the wall was primarily the work of the regular troops, the legionaries of the Second, Sixth and Twentieth Legions, who had come from Caerleon, York and Chester for the purpose. With them for minor duties and for patrol work were the auxiliary regiments, of various origin, who were to garrison the finished structure; and servile or semi-servile levies of native tribesmen also bore their share and left a record of their presence.

For a year or two the countryside must have been a hive of activity with a cosmopolitan, polyglot crowd of hewers and builders housed in the temporary earthen camps which can still be seen at many points outlined faintly on the turf. Moreover, on Fallowfield Fell, near Chollerford, at Haltwhistle Fell and elsewhere can be seen the actual quarries where the wall-builders found their stone and, incidentally, cut their names. "The rock of Flavius Carantinus," runs the Fallowfield inscription; and a quarry-side covered with Roman names near Brampton is known picturesquely as "The Written Rock of the Gelt."

The new forts, now seen to best advantage at Chesters and Housesteads, were of the normal Roman type, oblong in plan, with towers at the rounded corners and along the walls and one gateway (more rarely two) in each side. Straight streets joined the opposite gateways, save that the longer street was interrupted by the headquarters building, which included the regimental shrine and the strong-room or treasury-the latter, at both Chesters and Great Chesters (Aesica), still covered by its stone vault. Beside the headquarters building lay the granaries and the officers' mess, whilst before and behind it were the long lines of barrack blocks and stables. Beyond the defences was raised the bath building (again best seen at Chesters), which served also as a sort of regimental institute, whither the troops could resort in their leisure hours. Amongst the varied secular duties of the soldiery time had to be found for the housing and worship of the many gods-Roman, German, Gallic, British and Oriental-whose range was scarcely limited by the far-flung frontiers of the Roman world. From Persia came the cult of Mithras which was at one time a formidable rival to Christianity, and was probably always the more popular religion amongst the Roman soldiery of Britain. Below the Housesteads fort, on the shoulder of the Chapel Hill, a cave shrine to this deity, when first explored in 1828, contained many of its sculptures and altars still in position, including the representation of the miraculous birth of Mithras from the mystic egg. A few yards from the shrine, on the other hand, have been found altars bearing the unwieldy names of obscure German deities-the Alaisiagae, Bandihillie, Fimmilene, Thingsus, and others-brought by German levies from the Rhinelands and sometimes slightly naturalized by association with the Roman god Mars, or with the "Divinity of the Emperors." In some of these strange Teutonic deities it has been suggested that we should recognize the Valkyries and the German war-god of the skies; we are in any case in a religious world that was remote from that of Mithras.

Elsewhere, altars to Celtic deities be-tray the influence of Gaul or of the local cults of Britain. Such are those of Maponus, or of Belatucader; or of the Cocidius, whose name may still survive in that of the Northumbrian river Coquet. More Roman is the goddess of Fortune, whose altars, found often in the bath buildings of the forts, bear witness to the games of chance which formed one of the attractions of those places of resort. As a contrast, the regimental shrine within the defences would sometimes house a dedication to Discipline, which was there canonized as something more in actual fact than an abstract virtue.

So much, at the moment, for Hadrian's frontier. The province, however, as he left it was admittedly incomplete, and two more attempts were subsequently made to finish it. With the first of these we are here concerned, because it has left a permanent mark upon the land. This mark is, of course, the famous Antonine Vallum, which girdles the waist of Scotland from Bo'ness on the Firth of Forth to Old Kilpatrick on the Clyde, a distance of some 37 miles. Here again the scheme had in essence been anticipated by Agricola who, along the same line, had built a series of forts about the year 81.

These forts were small-that which underlies the Antonine fort at Bar Hill, west of Glasgow, was less than half an acre in extent-and they resembled the series on the Stanegate in the possession of no more substantial a link than a military road. They were clearly not designed to endure, and before the accession of Hadrian in a.d. 117 they had been abandoned.

In or about a.d. 142 the line of Agricola's forts was reoccupied; nineteen forts were built or rebuilt at intervals of about two miles, and the series was linked together by a rampart of turves, no less than 10 feet high, with a breadth of 6 feet at the top and a stone foundation 14 feet wide. In front of the rampart was dug a large ditch about 40 feet wide and 12 feet deep. The whole system, though less varied and certainly less impressive than that of Hadrian's Wall, was more closely knit and in some respects stronger.

The forts themselves are for the most part rather smaller than those of the English wall. At various times half a dozen of them have been partially or completely excavated, and the site at Mumrills, rather less than two miles east of Falkirk, is now being explored. They range from 1 to 4½ acres in extent, with the exception of Mumrills, which is somewhat larger and may have formed the headquarters of the whole frontier. Their defences consist sometimes of a stone wall and sometimes of a turf bank, fronted by two or more ditches.

A feature of certain of the forts which has not yet been recognized definitely in Hadrian's series is the presence of a fortified annexe, evidence of the comparative insecurity of the Scottish frontier. This annexe normally contained the main bath building of the fort, the workshops of some of the military artisans, and probably the hutments that housed the families of the garrison. Its size sometimes equalled or even exceeded that of the fort itself.

Not the least interesting feature of the Antonine Vallum is that the numerous Roman inscriptions found along it have enabled Sir George Macdonald to reconstruct the exact manner in which it was built. He has shown that it was begun at the eastern end, and that two working parties from each of the three legions of the Roman army "of occupation" were engaged upon it. These parties were of different sizes to match the varying lengths of vallum between the forts, and they doubtless worked in competition with one another. Indeed, the whole system of Roman military building seems to have been calculated to inspire a spirit of emulation amongst the troops.

In spite of its tactical strength, the Antonine Vallum suffered from a fundamental weakness. The greater part of the Lowlands which lay to the rear of it were never Romanised, and the frontier therefore remained "in the air." It was held only for forty years, and even during that short period it was twice overwhelmed and the forts largely destroyed. In or about a.d. 181 the end came. The contemporary Graeco-Roman historian Dio records that then "the tribes in Britain, having crossed the wall that separated them from the cantonments of the Romans, committed great havoc, and slew a Roman general with the soldiers under his command." The fury of the attackers has left enduring traces upon the fragmentary remains of the Roman forts.