3. The evidence of the marching camps
At the end of each day’s march the Romans created a fortification which involved the digging of a large defensive ditch and the building of a rampart around the four sides of the camp. The outline of these defences can still be detected on the ground today, leaving a footprint of each Roman incursion. These traces show us exactly where the Roman army was deployed in Scotland and gives us some indication of the various campaigns. If the battle of Mons Graupius did occur in Strathearn then it should be reflected in the archaeological evidence of these temporary marching camps.
Route of Invasion
The evidence of these camps shows the principal route of Roman invasion into northern Scotland went from Ardoch near Braco, to Bertha [Perth] on the Tay before moving through the north-east and towards the Moray Firth. If we look at the camps from Ardoch the initial Roman incursions north of the Forth appear to have begun with relatively modest forces that occupied 6 and then 13ha camps. These temporary marching camps were probably contemporary and of a Flavian date. Cutting through the Flavian defensive ditches a camp of 25ha then follows, possibly from the Antonine period, before the vast Severan camp of 53ha envelopes all three previous camps (St Joseph, 1970; Breeze, 1983). Therefore, this evidence suggests at least three successive incursions beyond the Forth involving armies of 13ha (19ha), 25ha and 53ha which may have been related to the three principal periods of Roman invasion: Flavian, Antonine and Severan. Each of these armies followed the same route north, crossing the River Earn at Strageath and then moving along the Gask ridge to the River Tay. The Tay was crossed at Scone, before each of these Roman forces proceeded towards the northeast, whereupon the line of camps becomes increasingly difficult to read and interpret. Nevertheless, it is generally assumed that if the battle of Mons Graupius occurred it was on this route, the marching camps of the north-east providing the most likely candidates. Yet, although this is the principal route of Roman invasion into northern Scotland, it is not the only route evidenced in the marching camps. There is a second series of marching camps apparently moving from east to west. In the attempt to find Mons Graupius little attention has been paid to these camps, although they appear to reflect a highly significant movement of troops.
The marching camps of Fife and Strathearn
This east-west line of camps first appears just south of the Severan Roman fort and naval base at Carpow, near Newburgh. It then moves west from Carpow to Carey beside Abernethy before proceeding down the Earn valley and inland to Dunning (St Joseph, 1969; 1973). Each of these camps shares very similar dimensions (approximately 690m x 660m) and occupies an area of around 44-46ha. At Carpow two gates have been identified each with a titulum, together with a V-ditch 4.5m wide and 1.5m deep forming a polygonal enclosure. A similar rhomboidal shape is seen at Carey where six gates with titulum have been revealed. There are two gates respectively in the north and south sides, with one located centrally in both the east and west sides (St Joseph 1974). This pattern continues with the marching camp at Dunning which has similar outline and a V shaped defensive ditch of equal width and depth to that found at Carpow and Carey. But thus far only three gates have been identified two in the north west corner and one in the south west each with titulum (CFA, 1993).
This Carpow-Carey- Dunning series of temporary camps dates from the Flavian period (69-96CE). Pieces of Samian pottery (Dr 27) from the first century CE and a coin from the reign of Titus (79-81) were discovered in excavations at the marching camp at Carey. Although in 1992 eleven joining shards of a mid-second century CE BB2 bowl (probably Antonine) were recovered from one of the trenches of the camp at Dunning other evidence supports an earlier date (CFA, 1993). The close proximity of what is believed to be an Antonine marching camp at Forteviot (25ha) probably explains the presence of this second century CE material at this site (St Joseph 1974). Thus the evidence from Carey strongly suggests that the original Carpow-Carey-Dunning line of camps should be read in a Flavian context. We, therefore, have evidence in these camps of a large deployment of Roman troops in Fife and Strathearn during the Flavian period.
Significantly the Carpow-Carey-Dunning deployment of troops apparently finds its terminus at Dunning. Although we cannot discount the possibility that some of the marching camps may have been lost, there is no sign of this Roman army either at Ardoch or having crossed the Forth. Neither is there evidence of this army on the Gask ridge or proceeding further north or heading south. The pattern of camps as we have it is consistent with a focused and deliberate Flavian campaign into Strathearn. The archeologically evidence shows a series of three marching camps beginning at Carpow and ending in Dunning, at the foot of Rossie Law.
Further evidence that Dunning was the terminus for this force is also suggested by the distance between the marching camps at Carpow and Carey. These camps are only three miles apart which is far less than a Roman day’s march of between eight and twelve miles. This relatively short distance between Carey and Carpow requires explanation. It is difficult to see why one would have gone to all the effort to create two marching camps so close together if it did not serve some strategic purpose.
One possibility is that the troop movement from Carpow to Carey left the Roman army with exactly a single day’s march to Dunning. As no other marching camps to date have been identified beyond Dunning this would suggest it was the focus of the deployment. It is also possible this anomaly provides evidence of an amphibious landing by the Roman army. The temporary marching camp at Carpow is only a few hundred metres from the Tay estuary. In the third century CE during the reign of Severus and his successors this site became an important Roman harbour and fort (c.208-220CE). Yet the presence of this earlier camp could suggest that Carpow was used as a Roman port or supply conduit prior to its development by Severus. There is no reason why the landing and supplying of Roman troops through Carpow could not have been occurring in the Flavian period. Gordon Maxwell has also drawn attention to a distinctive defensive ditch at Carpow which might be part of a beach-head (1998). Although no secure dating is possible such a beach-head would be congruent with the deployed of troops from the sea providing us with an explanation for the genesis of the Carpow-Carey-Dunning line of camps.
Therefore, the Carpow-Carey- Dunning series of marching camps is consistent with a sizeable deployment of Flavian forces apparently marching towards Dunning in Strathearn, possibly after having being deployed from the sea. Yet what could have elicited such a large deployment of Flavian forces in Strathearn and all the logistics involved in an amphibious landing? The coincidence in the deployment of this army and Ptolemy's Victoria makes a compelling case that we have here one of the most viable site for the battle of Mons Graupius.