- The Roman military depended on the rapid and efficient movement of its troops and the equipment and supplies required to maintain their effectiveness as a fighting force in the field. Playing a crucial role in this task was a complex network of roads laid down at an early stage during the Roman penetration of an area.
- The Roman road networks were established along major routes – probably long established – that utilised river valleys and upland passes where ease of travel meant both swift access for the Roman military personnel, and likely routes all which a potential enemy would launch an attack. Roman soldiers, billeted in nearby camps, would build the road themselves, along a line laid out by a surveyor. The road would follow the most direct route possible, which meant that long distances could be built with little if any deviation from a straight line. The surface would be metalled using material removed from quarry pits dug on either side, and in South West Scotland, would have measured between 5 and 8m in width. This allowed two wagons or carts to pass in opposite directions. The surface would be cambered to allow surface water runoff, and the composition varied to allow water to drain down through the metalling. Run-off might collect in a lateral ditch or pair of ditches. In marshy or waterlogged areas, rather than deviating around the obstacle, the roadbuilders would pile brushwood or brash beneath the layers of gravel and metalling, creating a floating mat to support the structure.
- Safety was an important factor, so Roman military sites formed nodal points at either end of a particular stretch of road or at a junction. In between these nodal points, a network of smaller fortlets like those identified at Durisdeer and Outerwards and even smaller watchtowers or signal posts like Craik Cross would be set up, ensuring that the route was always under surveillance. Signal beacons, maintained on these sites, would ensure almost instantaneous notice of dangers or difficulties further up or down the line.
- The Roman army was largely composed of infantry. They would march on foot between garrisons, carrying their armour and their weapons, covering around 20 miles a day. If their destination wasn’t an established fort, they would set up a temporary camp and dig a defensive ditch around the perimeter. All the baggage they needed, such as tents, handmills for grinding corn, cooking utensils and the like, would be carried by draught animals. Typically, the equipment of ten men would be assigned to one pack animal, which would require being stabled and fed for the duration of the campaign. Mules would be used as pack animals, and oxen would be used to pull carts or wagons. The oxen were often shod with iron ox-shoes, while equids might be equipped with hippo-sandals, flat plates of iron shaped for the hoof and clipped and tied into place. These would have protected the sole and the frog of the hoof against bruising from road metalling.
- Mounted cavalry would have played an important role amongst the Roman forces in South West Scotland. It is possible that the auxiliary troops stationed at Birrens at one point comprised a cavalry regiment raised in the Middle Rhine region. Detachments or cohorts of infantry would also have had a small contingent of mounted soldiers embedded within them, used for reconnaissance, scouting or delivering dispatches. Their horses were stabled within the perimeter of the fort, with spare animals present to allow for loss through injury or ill health. Finds of horse equipment from the site remain sparse, so details of these soldiers’ equestrian skills remain uncertain. Roman horsemanship involved the use of a very harsh bit which could injure the horse when used by insensitive hands; the only bits found locally in the vicinity of Birrens were of the much milder snaffle type, used by the indigenous communities for their chariot-ponies. It is possible that the Germans and Tungrians who were billeted would also have been using snaffle bits, reflecting their Celtic origins. Their horses wore harness which had decorative fittings of bronze, and the saddles had no stirrups; the rider was held in place instead by horned fittings at the front and back of the saddle, which kept the rider’s thighs secure and stable, particularly when their balance would have been challenged when wielding weapons or manoeuvring the animal at a fast speed.
- More intriguing are occasional finds of terrets from Roman military sites. These rein-guides would have been mounted on a yoke, typically used for the teams of two chariot-ponies which formed an integral part of the indigenous Iron Age culture. The Middlebie hoard of chariot fittings, recovered near Burnswark, has previously been attributed to Roman auxiliaries of Celtic origin, but an indigenous origin seems more likely. A similar terret, found in isolation, was however, recovered from the Roman fort at Drumlanrig, posing the intriguing possibility that indigenous metalwork may have been acquired by members of the Roman military, though for what purpose is unknown.
- So far, the emphasis has been on movement by land, and the road network which forms such a prominent feature in the study of the Roman occupation of Scotland. It should not be forgotten, however, that the Romans also had a strong maritime tradition, and it is quite possible that some vital supplies, like cereal grain, would have been transported over longer distances by sea. Roman galleys could be propelled either by sail or by oarsmen, the latter comprising enslaved persons.
- Confirmed harbour infrastructure has, however, so far proved elusive. A Roman temporary camp has been identified close to a coastal location at Ward Law, near the Nith estuary close to Caerlaverock. Girvan Mains and Ayr Academy are also located relatively close to coastal locations. Intertidal features were identified in the 1970s at Brigurd Point, near Hunterston, with finds of 2nd century AD ring-necked flagons from the Poteath Burn, West Kilbride providing additional evidence for a Roman presence in the form of material culture. Kenneth St Joseph argued that there may have been a Roman harbour facility at the mouth of the River Irvine at Irvine. Once again, this possibility is supported by material culture finds, this time in the form of two 2nd century AD Roman coins, reported in the 1980 Irvine burgh survey (Simpson & Simpson 1980), which infer activity during the Antonine campaigns.