Birdoswald Roman Fort

The Roman Fort at Birdoswald is constructed on a rocky spur, a perfect position that afforded additional protection to its southern flanks. However, in order to utilise this natural feature, the Romans had to employ considerable effort and ingenuity to first drain the land, and then construct their fort of turf and timber. The northern perimeter wall of Birdoswald Roman Fort would have been incorporated into Hadrian's Wall, also constructed of turf at that time. The Vallum (defensive ditch) still visible to the south of the later stone curtain wall was almost certainly intended to be used in conjunction with the early fort.

At some stage in the early second centruy a decision was taken to re-build Birdoswald Roman Fort in stone, enlarging it so that the north wall of the fort extended beyond Hadrian's Wall, thus creating a need for an east and west gate ajoining the Wall. Most forts of this type had four principle double-portal (arched) entrances set roughly in the centre of the four perimeter walls, but at Birdoswald Roman Fort the east and west entrances were off-centre leaving a large area of perimeter wall to the south with only a single gate in it. This resulted in the addition of two further gates in the east and west elevations, giving better access to the southern military zone.

Birdoswald itself is of standard Roman design, being roughly rectangular in dimension with rounded corners for greater strength. Originally the walls would have been some 14ft (4.2m) high to a wall-walk, and above that a crenellated parapet extending a further 6ft (1.8m) for the protection of the soldiers. Defensive towers were built at the four corners, and two of the bases can be seen at the north-west and south-east corners. Each of the gates would have had defensive towers, the main double gates having a tower at each side of the opening, and the two additional single gates having a tower constructed above.

Several of the internal buildings were known to have been constructed at this time, four of which were to the north of the wall line. Two of these were long rectangular buildings that were probably used for storage. The foundations of one, though subsequently altered, can be seen immediately in front of the existing farmhouse, but the other one lies further east and has since been re-buried. The most surprising find at Birdoswald Roman Fort was a Basilica, a large aisled hall used for drill practice and exercise that was located in the north-west quarter of the fort. It is unique, inasmuch as no building of this type has ever been found within a fort of the Roman Empire, but the majority of this structure has since been covered by the farmhouse. In 1929 a barrack block was excavated, lying just beyond the eastern store building in the north-east quarter, but this has also been re-buried. The contours of a fifth building can still be made out near the eastern gate, and this would have been the headquarters building. It is presumably Hadrianic in origin, but as it has never been fully excavated the details remain uncertain.

Around the time of Hadrians death, cAD138, the final 'Hadrianic' phase of building was the reconstruction of the turf wall in stone. The line of the new stone wall was moved north so that it joined Birdoswald Roman Fort at its northern corners, in a similar manner to the original turf and timber fort, and as a result of this the additional eastern and western gates were removed and blocked up.

The two Granaries built in the early part of the third century are the largest surviving internal structures at Birdoswald Roman Fort, and are similar to those found at Corbridge much further east. Substantial in construction, the buildings had raised floors to ensure good ventilation of the grain. During this building phase the westernmost Hadrianic storehouse was also portioned off to form a series of workshops. When the garrison was scaled down in the 4th century, the original barrack block and storehouse in the north-eastern quarter of Birdoswald Roman Fort was converted to an officer's house.