Guarding the crossing of Hadrian’s Wall over the River Irthing, Birdoswald Roman Fort was initially a turf and timber construction. It was rebuilt in stone soon after and remained garrisoned until the end of Roman Britain in the Fifth Century. Even then, life at the fort seems to have continued and it may have been used as a high status residence for a local chieftain.



By the early second century AD Roman forces had been in Britain for almost sixty years but, although successful campaigns had been waged in the far north of Scotland, military cutbacks had meant the northern extremity of their occupation had settled upon the Stanegate Road which ran between the River Tyne and the Solway Firth. For many Romans continued expansion north would have seemed inevitable but all that changed with the accession of Emperor Hadrian in AD 117. He embarked upon a radical policy of entrenchment and consolidation creating physical borders across the Empire, a concept previously alien to Roman ideology. In Britannia, which he visited in AD 122, he ordered the construction of Hadrian's Wall - a substantial frontier system constructed to the north of the Stanegate Road. The site of Birdoswald, which occupied a prominent position overlooking the River Irthing, lay upon the line of this new frontier.


When Hadrian's Wall was initially constructed, the section to the west of the River Irthing was constructed from turf and timber with free standing stone turrets. One of these turrets (today classified as 49A) was built upon the Birdoswald site and both the turf rampart and the associated defensive ditch were connected soon after. A temporary camp, presumably for the soldiers engaged in construction of the frontier, was established on the cliff edge overlooking the river. However, after this work had been completed, the Romans changed their plans. The original intent had been for the garrison of the frontier to remain in their forts upon the Stanegate Road but instead the decision was taken to build new forts upon the Wall itself at intervals of around 7 miles. Birdoswald was chosen as the site of one of the new forts and also became a key junction on the Roman Road network as the Maiden Way, one of just three Roman Roads that projected north of the frontier, ran through the site.


The first Birdoswald Roman Fort was built around AD 125 and straddled the Wall with its north, west and east gateways all offering access beyond the frontier. Constructed in the standard 'playing card' layout, the fort enclosed just under four acres and was designed to house a Regiment of around 500 men. The Vallum, a substantial earthwork that ran parallel with Hadrian's Wall and created a 'military zone', was clearly added after the fort as it adjusted its line to take into the account the space occupied by the facility. The first unit assigned to the outpost is believed to have been the First Cohort of Tungrians (Cohors Primae Tungrorum), a 1,000 strong unit drawn from Southern Belgium. However this unit would have been too large for the site and was probably split between Birdoswald and the next fort to the west at Castlesteads. This arrangement has however caused some confusion as to the Latin name of Birdoswald. A fort called Banna is attested to in contemporary documentation between Stanwix (Carlisle) and Great Chesters but it was unclear whether this was referring to Birdoswald or Castlesteads. This has vexed historians but the issue now seems to have been settled by the discovery of a variety of contemporary Roman souvenirs that listed the forts along the Wall and detailed both Castlesteads (as Camboglanna) and Birdoswald (as Banna). The name of the latter is derived from the Gaelic word 'peak'.


Around AD 130 Birdoswald fort was rebuilt in stone and significantly expanded forcing the Vallum to be filled in accommodate the increased size. The new fort enclosed an area of over five acres but again was configured in a standard playing card layout. Substantial upgrades were also made to the frontier at this time with the rebuilding of the entire Western section in stone. At Birdoswald the rebuilding was underway no later than AD 138 and here the line of the Wall was moved slightly north meaning only the fort’s north gate now projected outside the frontier. Shortly after however, following the death of Hadrian in AD 138, the decision was made to abandon the Wall and Roman forces once again advanced into Scotland where a new frontier established on the Antonine Wall. Little is known as to what became of Birdoswald during this time. Its key location on the Maiden Way, a key road north towards Bewcastle, means it may have continued to be occupied and some archaeological evidence supports this.


The Antonine Wall was only occupied for around twenty years before the frontier was returned to Hadrian's Wall. Substantial rebuilding was conducted at Birdoswald at this time and a new Regiment, the First Cohort of Thracians (Cohors Primae Thracum), was assigned to the outpost no later than the early third century AD. This regiment was originally recruited from the area around Bulgaria and was a mixed cavalry/infantry force. No later than AD 219, the garrison at Birdoswald was changed to the First Cohort of Aelian Daci (Cohors Primae Aelia Dacorum). This was a 1,000 strong infantry Regiment originally recruited from Romania although by this time it is also likely that many of its men were locally recruited. With the peaceful conditions along the frontier at this time, a substantial civilian settlement  (vicus) developed outside the fort predominantly to the west but houses were also built immediately to the north, beyond the Wall. It is mooted that St Patrick may have originated from this settlement before he was captured by Irish pirates and sold into slavery. In his later writings his place of origin as Vicus Bannaventa Berniae implying a fort known as Banna with a settlement attached. He also stated that his father served as a decurion in a nearby city for which Carlisle would seem to fit.


Roman control of Britannia broke down in the early fifth century AD severing Birdoswald's garrison from the Imperial supply chain and the money that flowed from the central treasury which paid the soldiers. Despite this, life in the fort seems to have continued although it was undoubtedly on a smaller scale. Little is understood about life in the fort at this time but it is telling that as the Granary buildings decayed they were replaced by long timber halls with hearths suggesting a high status residence. It is tempting to imagine that the Roman garrison simply morphed into a war band and its commander into a chieftain. As the economy moved towards a barter basis, perhaps some trappings of Roman grandeur helped legitimise this chieftain’s grasp on the local area.


Occasional references are made to Birdoswald in the Middle Ages as part of the Barony of Gilsland. Certainly in the thirteenth century one Radulpho de Birdoswald owned the site and his surname suggests it was also his residence. However, by the fifteenth century the area was plagued by the Border Reivers. These thieves, murderers and bandits used the rough terrain of border country to raid and pillage. By this time Birdoswald was owned by the Vaux family who built a tower house near the west gate. This was replaced by a bastle house, a defendable farmhouse, during the sixteenth century. The accession of James I (VI of Scotland) in 1603 saw the Border Reivers suppressed and antiquarians had started to take an interest in the ruins.  The farmhouse was added in 1745 and extended in 1858.




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Breeze, D.J (2002). Roman Forts in Britain. Shire Archaeology, Oxford.

Burton, A (2010). Hadrian's Wall Path. Aurum Press Ltd, London.

Campbell, D.B (2009). Roman Auxiliary Forts 27BC-AD378. Osprey, Oxford.

English Heritage (2010). An Archaeological Map of Hadrian's Wall, 1:25,000 Scale. English Heritage, London.

Fields, N (2005). Rome’s Northern Frontier AD 70-235. Osprey, Oxford.

Historic England (2015). Birdoswald Roman Fort List entry Number: 1010994. Historic England, London.

Historic England (2015). Birdoswald Farm House List entry Number: 1249314. Historic England, London.

Moffat, A (2009). The Wall. Birlinn Ltd, Edinburgh.

Ordnance Survey, Historic England and RCAHMW (2016). Roman Britain. 1:625,000 Scale. Ordnance Survey, Southampton.

Shotter, D (1998). The Roman Frontier in Britain. Carnegie Publishing Ltd, London.

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Wilmott, T (2010). Birdoswald Roman Fort. English Heritage, London.

What's There?

Birdoswald Roman Fort offers a superb starting point for exploring and understanding Hadrian's Wall. The fort was garrisoned throughout the occupation of the frontier and substantial masonry remains offer a good insight into the layout of this Auxiliary manned outpost. The fort is connected to one of the longest surviving continuous stretches of Hadrian's Wall and the well preserved Milecastle 49 (Harrows Scar) is only a short walk (under one mile) to the east as are the remains of the Roman Bridge over the River Irthing. For a much longer walk please see our guide to all surviving remains of the Wall!

Development of Birdoswald Roman Fort. In the initial plan for the frontier there was no fort at Birdoswald and instead Turret 49A and a Signal Tower were built on the site as was a temporary Roman camp which was probably used to support the construction of the Wall. In the mid-AD 120s the plan for the Wall was changed and forts were built upon its length. Turret 49A was demolished and a turf-and-timber fort was constructed on the site with the Vallum, the defensive earthwork that ran to the south of Hadrian's Wall, being added shortly after. Around AD 130 the fort was enlarged and rebuilt in stone. A few years later Hadrian's Wall itself, which to the west of the River Irthing had been a turf and timber construction, was also rebuilt in stone and in this area only the line of the frontier was moved slightly further north meaning Birdoswald no longer straddled the line.

Roman Fort Layout. Roman forts of the first and second centuries generally conformed to a 'playing card' layout, i.e. they were rectangular with rounded corners.

West Gate and Farm House. The West Gate was extensively modified over the years and was the site of the Tower House and later Bastle in the medieval period. The farm house was built in the eighteenth century.

Granaries. Roman forts had granaries to store provisions through the Winter months to ensure the garrison could sustain itself should the weather frustrate resupply operations. At Birdoswald these were rebuilt long after the Romans left into some form of timber hall. The wooden posts mark the extent of this structure which was probably a high status residence for a chieftain.

Beyond the Fort. Birdoswald offers a superb place from which to explore Hadrian's Wall. Whilst the remains lack the awe-inspiring terrain further to the east along the Whin Sill, the components of the frontier can be seen in a short walk from the fort. Photographs above are the River Irthing as seen from Birdoswald Roman Fort (left), the remains of the bridge over the River Irthing (centre) and Milecastle 49 (right).

Getting There

Birdoswald Roman Fort is located in Gilsland just off the A69. The site is a major tourist attraction and is well sign-posted. There is a large pay-and-display car park in the vicinity.

Car Park


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Birdoswald Roman Fort


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Milecastle 49 (Harrow's Scar)

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River Irthing Bridge Abutment

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