In 2008 archaeological excavations were undertaken by AOC Archaeology Group prior to the commercial development of an 18 ha site at Newbridge, Edinburgh ( fig. 1). The Early Bronze Age barrow and associated standing stones at Huly Hill and the Newbridge Iron Age cart burial lie just to the south of the development site.Footnote 1 The excavations revealed more of this prehistoric landscape.Footnote 2 Post-built roundhouses of Middle Bronze Age date were clustered in the middle of the development area, while in the south there was a cluster of ring-groove structures, some of which yielded pre-Roman Iron Age dates ( fig. 2, Structures 4 and 5). Scattered across the area were the ditched field boundaries and rig-and-furrow of medieval agricultural activity, probably associated with a settlement to the north of the excavated area. One of the large ring-groove structures (Structure 8) was associated with a stone-filled hollow which curved around its southern walls, forming a working platform of sorts ( fig. 2). A double-flued fire-pit which yielded two Iron Age dates (390–180 cal bc – SUERC-30039; 360–50 cal bc – SUERC-30040) had been constructed within the hollow. Cutting across this stone-filled hollow was a length of metalled cobble road flanked by stone kerbs which, given its size and mode of construction, is thought to be Roman. A more truncated segment of the road lay along the same alignment to the east.
FIG. 1. Location map, showing other sites mentioned in the text.
FIG. 2. The western and eastern segments of the Newbridge road, cutting across the remains of an unenclosed prehistoric settlement.
THE ROMAN ROAD
The two segments of the road were aligned WNW–ESE and in total covered a distance of roughly 67 m ( fig. 2: the grid reference at the central point between the two segments is NT 123 728). The western segment, which ran over the stone-filled hollow, was the better preserved. It had survived for a length of 21 m and was 7 m wide, flanked by kerbs of large, unbonded stones; the southern kerb was intact but only a short length of the northern kerb had survived. The stone-filled hollow appears to have been used as a foundation, over which smaller cobbles and a compact silty sand, 0.17 m in depth, had been laid ( fig. 3). Above this, a metalled surface had survived in patches over the agger.
FIG. 3. Section across the western segment of the road.
The eastern segment of the road had been more heavily truncated by modern and medieval agricultural activity and the stone matrix dispersed across the fields. It survived as a roughly diamond-shaped spread 21 m across and up to 7 m wide, with only a short 3 m length of the southern kerb still in situ. Nonetheless, the structure of the road was still clear; a foundation of medium-sized cobbles over which a compact silty sand and then a metalling of gravel had been laid; these uppermost surfaces surviving only very patchily.
Two large pits, one immediately to the south of the western segment and the other some 20 m to the north of the projected westward extension of the road, may represent quarry pits associated with the construction of the road.
DISCUSSION
There is no independent evidence for the Roman date of the road. If, as is argued, the fire-pit was an integral part of the stone-filled hollow, then the Iron Age dates from this feature provide a terminus post quem for the construction of the road, while one of the medieval ditch boundaries cuts across the eastern segment, providing a terminus ante quem. Lack of dating evidence aside, the remains uncovered at Newbridge do fulfil the structural criteria for Roman roads outlined by both Margery and Davies.Footnote 3
The Newbridge road was ‘hard bottomed’, a characteristic of more Roman roads in the North and West than elsewhere in Britain.Footnote 4 The large stones in the hollow were used as a convenient foundation deposit, over which a layer of smaller stones was laid. A layer of similar small stones forms the foundation of the eastern segment of the road. Similar foundation deposits of small stones have been recorded in the roads excavated at the forts of Inveresk and Cramond;Footnote 5 Davies suggests that it might have been a method of construction favoured by military road builders.Footnote 6 A distinctive feature of the Newbridge road is its kerbs. These are not a common feature on Roman roads, but those that have them are concentrated in northern England, Wales and Scotland, probably because of the availability of suitable stone.Footnote 7
The presence of an agger and surface metalling are good indicators of Roman road construction. The western segment exhibited a pronounced agger, with extensive patches of metalling surviving between the two kerbs. The width of metalling present is the main criterion in determining the traffic-carrying capacity of the road and is, therefore, a key indicator of both its importance and function.Footnote 8 Dere Street, the main Roman supply route between northern England and eastern Scotland, is 7.7 m wide on average. This compares well with the 7 m width of the segments at Newbridge. Wider roads in northern England and Scotland are seen as indicative of greater Roman military activity in these regions.Footnote 9 The agger was often formed from local materials excavated from drainage ditches running parallel to the road. At Newbridge these ditches were absent, probably because the free-draining sands and gravels of the local geology made them unnecessary. The two large pits found on either side of the road may have supplied the material needed to construct the agger.
A westerly extension to Dere Street, connecting the eastern terminus of the Antonine Wall with the main supply route from northern England, has long been proposed by authorities such as Lawrence Keppie and Gordon Maxwell.Footnote 10 The discovery of a milestone and two temporary marching camps west of Edinburgh have long suggested that this route lay inland rather than following the coast.Footnote 11 The Ingliston milestone, dedicated to Antoninus Pius, was discovered in the late seventeenth century on the east bank of the river Almond in a ‘plain field, near to which severall Obelisks are to be seen’, in all likelihood these are the standing stones associated with Huly Hill.Footnote 12 Maxwell argued that the milestone had been found at or near its original position close to a major Roman artery of communication, and cited the presence of the two Roman temporary camps at Gogar, just west of Edinburgh and some 5.5 km east of Newbridge, in support of his argument that Dere Street continued west of Edinburgh.Footnote 13 He suggested that the road might have crossed the river Almond ‘in the vicinity of Newbridge or Kirkliston’.
Newbridge is and always has been a natural focus for east–west travel routes; it lies at what is a nexus of major routeways to this very day ( fig. 1). It lies just north of where the river Almond emerges onto the coastal plain, at one of only two crossing-points along the river. The discovery of the Roman road at Newbridge thus provides solid evidence for the routeway that the Ingliston milestone and the temporary camps at Gogar have long intimated. The discovery of the road at Newbridge not only extends Dere Street westwards towards the Antonine Wall, but also provides a link with the wider network of Roman roads in Scotland; that is those sections of road north of the Antonine Wall which have always been assumed to connect the forts of the Gask Ridge with the supply line.Footnote 14
ACKNOWLEDGEMENTS
The excavations at Newbridge, the post-excavation programme and the preparation of this note were funded by Rooster II LLP.
