Birdoswald Roman Fort: post-Roman activity on the site

Location of Birdoswald

Birdoswald is a Roman fort on Hadrian's Wall in north-west England. It's the sixth fort from the western end of the Wall, sitting on the western edge of the Pennines where the hills start to roll off into the plain of North Cumbria and the Solway Firth. The fort site itself is strategically located on a steep-sided promontory formed by a deep meander of the River Irthing, with wide-ranging views in all directions. It occupies the western end of the communication route across the Pennines formed by the valleys of the Rivers Irthing and Tyne, and commands the crossing of the River Irthing at Willowford.

Map links

Birdoswald - Streetmap

Birdoswald - Google Maps satellite image

The location was compared to Troy by a romantically-minded eighteenth-century Earl of Carlisle and an estate agent trying to sell the property in 1901. Like most such comparisons a large grain of salt is required - I can't see many people arriving at Troy, either Homer's legendary city or Schliemann's Hissarlik, and saying "Lo, behold the Birdoswald of Asia Minor!" Nevertheless, it's an impressive, if rather rain- and windswept, site. Scroll around and zoom in and out of the map and satellite image links to get an idea.

Place name

The Roman name of the fort was Banna, attested by an altar found at the site in 1821 and dedicated to the woodland god Silvanus by the 'Venatores Bannienses', which translates as 'the hunters of Banna'. Until recently it was thought to have been called Camboglanna*; however this is now thought to have been a mistake in the Notitia Dignitatum (Wilmott 2001 p. 97).

The modern name Birdoswald is first recorded as 'Burthoswald' or 'Bordoswald' in 1194-1220, when charters granted land there to the Priories at Lanercost and Wetheral (Wilmott 2001 p. 131). The name elements consist of the Old English man's name Oswald and the Brittonic (Welsh) element 'burth' or 'buarth', meaning a pen or farmyard (Ordnance Survey glossary of place name elements), so the name means 'pen or farmyard of Oswald'. The name elements are ordered in the Welsh format, with the personal name second (Old English names are typically ordered with the personal name first, in the format 'Oswald's farm'). This suggests to me that the name was coined and established by people who spoke Welsh or its Brittonic ancestor.

The most famous Oswald associated with the approximate locality is the seventh-century king of Northumbria, killed in battle in 642 and revered as a saint (Bede, Book III ch. 9), but as far as I know there's absolutely nothing to connect him with Birdoswald except the obvious romantic appeal of such a notion. Incidentally, I don't think the 'buarth' element of the name necessarily rules out a royal or aristocratic connection. Assuming that the 'pen' meaning of 'buarth' meant a livestock pen, a place where animals could be corralled, it could refer to the gathering of livestock for payment of tax or tribute as well as to agricultural use.

Post-Roman occupation at Birdoswald: the timber halls

The buildings visible in the north-west corner of the fort on the satellite image are those of the Georgian and Victorian farm, now a modern visitor centre. Occupation at Birdoswald is attested - though not necessarily continuously - from the Roman period to 1984, when the last farming tenants moved out. Much of the information we have comes from a series of excavations led by Tony Wilmott in 1987-1998 (for a fascinating, detailed and very readable account, I highly recommend his book on the subject, see references for details).

For the purposes of this post, I'll focus on the post-Roman phases of construction and occupation at Birdoswald on the site of the former fort granaries, discovered and excavated in 1987.

The Roman fort at Birdoswald had two large stone granaries, built between the central headquarters building (principia) and the west wall, south of the west gate (see sketch plan A). The exercise basilica or indoor drill hall (which must have been a welcome facility in rainy north-west England) and a long rectangular building of uncertain function stood opposite the granaries, north of the west gate (for pictures of the reconstruction of the slightly smaller exercise basilica at Saalburg in Germany, see The Lost Fort blog). The granaries were built some time in the second century (date uncertain) and repaired or rebuilt according to an inscription in 205-8. Around the same time, early to mid third century, the south portal of the west gate was walled up (Wilmott 2001 p. 93), leaving the north portal in use.


Sketch plan of the location of the Roman granaries in Birdoswald fort (A) and of the second-phase post-Roman timber hall in relation to the north granary (B)

The stone roof of the north granary collapsed at some time after 350, dated by a coin of 350-353 found beneath the drifts of fallen roof tile, and the ruins were then used as a rubbish dump (Wilmott 2001 p. 118).

The south granary had a new stone floor laid (dated by the coins found beneath the floor, which cease in 348) (Wilmott 2001 p.119). This floor later became covered with deposits of silt interspersed with patches of stone, and two successive hearths were built at the western end. Around the hearths were found a fourth-century glass finger ring, a gold and glass earring, and a worn coin from the reign of Theodosius (388-395) (Wilmott 2001 p. 121). The hearths indicate residential use, the jewellery suggests the presence of women, and the presence of jewellery and a coin indicates high-status occupation. This is consistent with the south granary being used at this period as something akin to a chieftain's hall. The jewellery, coin, hearths and stone floor were found beneath a layer of collapsed stone roof tiles, indicating that the roof fell in some time after the date of the coin (Wilmott 2001 p.121).

The north granary had been used as a rubbish dump after its roof collapsed, and the rubbish deposits included coins dated to the 380s and two penannular (ring) brooches of a type dated to the very end of or just after the Roman period in Britain (Wilmott 2001 p.121). A new flagstone floor was laid on top of these deposits, and shallow post-holes were made in the tops of the surviving walls by removing a few stones from the wall core. At the western end, the post-holes continued beyond the end of the original granary structure, encroaching on the Roman street. This suggests that the north granary was rebuilt as a timber building, re-using the remaining Roman walls as foundations (Wilmott 2001 p. 121). This timber building was the same width as the Roman granary and a little longer, and was therefore a large building, something like 25-30 m long. This is comparable with the size of the fifth/sixth century hall excavated at South Cadbury (though a different shape; the South Cadbury hall was 10 m x 20 m, while the Birdoswald granary was longer and narrower), so it was big enough to be the hall of an important ruler. It must have been built after the 380s on the evidence of the coins beneath the new flagstone floor. If it was the functional replacement of the "chieftain's hall" in the south granary, then it was presumably built at or after the time of the roof collapse in the south granary.

At some later date, this timber hall constructed mainly on the foundations of the north granary was replaced by a second timber building with a different footprint. This second timber building was also hall-sized, 23 m by 6.8 m, and was built partly over the site of the granary and partly over the adjacent street to its north (see sketch plan B). On the street, a line of stone post pads that would have supported timber posts were laid on the street surface, and on the granary shallow trenches were cut into the floor and stone post pads laid on the bottom of the trenches (Wilmott 2001 p.121). The north wall of this second timber building aligned with the centre pillar of the west gate; as the south portal of the gate had been walled up in the Roman period (see above), the hall was now lined up about as closely as it could get to the current entranceway, and would have been the first structure seen by anyone entering through the west gate (Wilmott 2001 p.121). (Constructing a hall directly opposite the gate would probably have been difficult because of the rectangular building and the exercise basilica on the north side of the street. Whether the exercise basilica was still intact or partly ruined by this date, its massive walls and pillars would presumably have constrained any subsequent construction for some considerable time).

Both these big timber halls on the site of the north granary were associated with smaller timber buildings built against or close to the western fort wall, south of the west gate.

Other post-Roman evidence from Birdoswald

There is no definite archaeological evidence from Birdoswald between the post-Roman timber halls described above and one medieval pottery sherd from the twelfth/thirteenth century (Wilmott 2001 p. 129, 135). All there is from this intervening period is:

The Anglo-Saxon brooch and pin could indicate contemporary trade contacts, conquest, loot, travel, occupation, marriage links or many other interpretations besides, or perhaps just a casual loss at some much later date. It's impossible to read much into two isolated finds; the most that can be said is that they are not inconsistent with early medieval occupation or activity at Birdoswald, perhaps extending beyond the likely date of the post-Roman timber halls.

A long cist grave is essentially a stone box or coffin constructed within the grave, usually from stone slabs. As far as I know they are usually associated with early Christian sites in Britain, and Ken Dark considers them to be an indicator of a late/post-Roman Christian culture that spread in the fifth and sixth centuries to areas that had been outside or on the periphery of Roman Britain, such as Wales, Cornwall and the region north of Hadrian's Wall (Dark 2002). Long cists are widespread in fifth- and sixth-century cemeteries in south-eastern Scotland (Dark 2002, p. 203), which is not so very far from the Birdoswald area. Furthermore, the centurion's quarters at the end of one of the barrack buildings in the north-west corner of Birdoswald fort was remodelled some time in the late fourth century and acquired a rounded west end (Wilmott 2001, p. 119). This may be an apse, which in turn may indicate that the building was being used as a Christian church, which in turn may indicate that at least some of the occupants of the fort were Christians. A single long cist grave, undated, could mean almost anything. Again, about the most that can be said is that it would not be out of place for an early medieval Christian living at Birdoswald to be buried in a long cist grave.

How long did the post-Roman occupation of Birdoswald last? More on this in another article.


Bede, Ecclesiastical history of the English people. Translated by Leo Sherley-Price. Penguin Classics, 1968, ISBN 0-14-044565-X.

Dark K. Britain and the end of the Roman empire. Tempus, 2002. ISBN 0-7524-2532-3.

Ordnance Survey glossary of place name elements, available online

Wilmott T. Birdoswald Roman fort: 1800 years on Hadrian's Wall. Tempus, 2001. ISBN 0-7524-1913-7.


* Camboglanna is now thought to refer to the next fort west, at the modern site of Castlesteads. Camboglanna is one of the candidates for King Arthur's (legendary?) last battle at Camlann, favoured by proponents of a northern location for King Arthur.