For a site that was first discovered in 1867 and partially excavated in 1869, it took a long time for the full significance of the Llangorse Crannog to be recognised by archaeologists. This small wooded island, roughly rectilinear and measuring some 40m by 30m, lies close to the north shore of Llangorse Lake (Llyn Syfaddan in Welsh), the largest natural body of water in south Wales. The lake lies in a basin east of Brecon, with the sandstone scarps and ridges of the Brecon Beacons rising to the south and west, and the Black Mountains to the east.

In a report to the British Association for the Advancement of Science published in 1870, Henry Dumbleton stated that ‘until two years ago, no idea was entertained that this [island] had anything remarkable about it’, but the summer of 1868 had been exceptionally dry, and the lake level very low, and oak planks had been observed in the lake close to the water surface. Henry and his brother Edgar also recognised that the rocks making up the base of the island were not laid in natural bedding planes, and were quite different in composition from those of the nearby lake shore. Moreover, when they removed some oak piles, they found tool marks and pointed tips. In their lectures and brief published papers, the two brothers compared the island to ‘the remains of habitations raised on piles, as well as upon artificial islands [that] have been found in several of the lakes of Switzerland and Italy’. This identification was vindicated by John Lee, the local Monmouthshire antiquary, who translated Keller’s classic Swiss Lake Villages volume into English, though in the absence of dated artefacts he warned against assuming that Llangorse was as old as the Continental sites.
Based on Dumbleton’s account, Robert Munro, author of The Lake-Dwellings of Europe (1890), accepted the Llangorse Crannog as genuine, ‘constructed after the manner of the Scottish and Irish crannogs’. He interpreted Llangorse as older than the Scottish or Irish examples because of his belief that lake dwellings were introduced into Britain from Europe by ‘the Celts’ who, having been ‘displaced by later invading Belgae, retreated to Scotland and Ireland and continued their crannog-building traditions’.

Dating the crannog
Several decades passed before the crannog was again the subject of archaeological scrutiny. In 1925, Cyril Fox, then Keeper of Archaeology at the National Museum of Wales, published his study of a logboat that had been found about 400m east of the crannog. Tom Jenkins, a local carpenter, had first spotted the boat some 20 years previously, but now he took advantage of the low level of water in the lake to lift it out for a closer look. Once he reported it to the National Museum, rapid measures were taken to stop it drying out, shrinking, and cracking by keeping it damp with wet sacks – the preserved boat now forms the star exhibit in the new y Gaer library, museum, and art gallery, which opened in Brecon in December 2019.

On stylistic grounds, Fox surmised that the logboat (and by association the crannog) was probably Late Iron Age to Romano-British in date, and this is how it was described when surveyors from the Royal Commission on the Ancient and Historical Monuments of Wales visited and recorded the site in the 1970s. Some doubt as to the accuracy of this date must have been in the mind of Leslie Alcock (author of Arthur’s Britain: history and archaeology AD 367-634 and a pioneer of the archaeology of what was then called ‘Dark Age Britain’), though, because he encouraged Alan Lane to take a closer look at the crannog as part of the research that Alan, along with Ewan Campbell, was undertaking in the 1980s for their book Early Medieval Settlements in Wales AD 400-1100 (1988). Reluctant as many archaeologists are to link their sites to historical people and events, Lane and Campbell were well aware of Brecon’s legendary origins as an early medieval kingdom founded by Brychan Brycheiniog, son of the Irish King Anlach, and pointed to connections with 5th- to 7th-century Ireland, where early medieval crannogs are abundant (see CA 299 for an example in Co. Fermanagh, Northern Ireland).

In 1988, Lane and Campbell decided to take a team from Cardiff University to survey the island and to plot the visible timbers. They took three samples for dating, and the result – placing the felling of the timbers between AD 860 and 906 – was later than the expected 6th- to 7th-century date, when many Irish crannogs were constructed. It was consistent, however, with charter evidence published by Wendy Davies in 1978-1979: the Llandaff charters 146, 154, 157, and 167 all refer to kings of Brycheiniog, and suggest a royal and monastic presence in the Brecon area from the early to mid-8th century, while land grants and boundary clauses attached to the charters (at a later date, but probably based on much older records) identify features in and around Llangorse that can be traced today, comprising an estate of some 400 hectares.
The archaeological potential of this waterlogged site was clear, as were the risks from natural erosion, boating activity, and fluctuating lake levels. Surveying and excavating in a lake posed technical challenges, but Mark Redknap, an experienced underwater archaeologist recently appointed Curator of Medieval and Later Archaeology at the National Museum of Wales, proposed a partnership project to investigate off- and on-shore. The subsequent joint museum/university surveys and excavations (1989-1994 and 2004) resulted in the recovery of some remarkable finds, the detailed evidence for which is presented in the newly published Llangorse Crannog report (see ‘Further reading’).

Construction, occupation, and destruction
The investigations found that the crannog’s construction was complex and well-organised. Its distinctive palisade planks had been driven into the peat and shell marl deposits lying on the base of the lake, penetrating the lake bed by a metre or more. These oak planks formed a palisade that probably rose a good 2m above the waterline in order to define the site and protect its occupants. Prior to this, a series of a post-and-wattle fences had also been driven into the lake bed, and the spaces delineated by the fences had been packed with carefully laid bundles of roundwood branches to create a raft. Substantial oak beams, each representing quarter of a tree trunk, were then placed on top of the raft and secured by posts driven into the lake bed. Finally, a mix of clay and red sandstone boulders, some slab-like, were laid to create a solid platform on top of the timber substrate.

Four extensions were subsequently built to the south and west of the first platform, eventually doubling the floor area of the crannog. It is not known how much time elapsed between each platform extension, but it is possible that it was only a year. The island was linked to the northern shore of the lake by a bridge made by driving posts into the lake bed in groups of three, spaced at 2.5m intervals, which served as the supports for joists and planking. No evidence survived in the limited areas available for excavation to indicate the likely form or appearance of the buildings that were constructed on top of the crannog platform, but parallels from elsewhere suggest a rectangular hall or halls, with reed-thatched roofs.

Dendrochronology and carbon dating showed that the site was occupied from the AD 890s. Charred artefacts and timbers, heat-affected stones, and an abundance of charcoal testify to the destruction of the crannog by fire, probably as the result of an event recorded in the Anglo-Saxon Chronicle for AD 916 when ‘Æthelflæd sent an army into Wales and destroyed Brecenanmere, and captured the king’s wife and 33 other persons’. We do not know what provoked Æthelflæd (AD 870-918), the eldest daughter of Alfred the Great and de facto ruler of Mercia from AD 902 until her death, to attack and destroy the crannog, though it is possible that this was punishment for some act of disobedience that did not conform to Mercia’s idea of the proper behaviour of a client kingdom.
A high-status household
In any event, Llangorse Crannog appears to have been a royal site, and the organised construction of the island, the careful design, the supply of timber, and the tons of stone, all reinforce the idea of elite control of local resources and human labour. Among the artefacts from the site, strap-guides and strap-ends speak of horse-ownership, and the large quantity of deer bones hints at the aristocratic love of hunting. Among the 21 copper-alloy small finds are two pieces from a portable house-shaped reliquary, decorated with red and yellow enamel and blue-and-white millefiori glass. One pseudo-penannular brooch terminal is beautifully crafted – adorned with interlace, simplified animal heads, and egg-and-dart patterning, it belongs to a class of ‘Irish-style’ brooches of the 8th and 9th centuries. Another survives in the form of a terminal shaped like a beast head, while a further beast head features on the bronze terminal of a drinking horn.

Bone combs, glass beads, and dress accessories all point to the high status of the site but, intriguingly, there is evidence too for the manufacture of metalwork at the crannog, in the form of 538 pieces of slag, hearth lining, fired clay, crucibles, and metal-working residues. Most of this can be linked to iron-working, but a significant amount testifies to the casting of bronze alloys. These finds suggest that high-status sites might have been used for forging, casting, and brazing, and that highly skilled craftworkers formed part of the elite household (as they do later in history: for example, the armourers employed to this day by the monarch). There is no evidence that metalworkers were permanently resident on the crannog, but Mark Redknap and Peter Northover say it is possible that ‘such creativity was the result of a long-standing relationship between patrons and metalworkers’, with luxury goods being made to order on the spot, for use by rulers and their families, or for gift-giving.


Further evidence of elite gift exchange was found in the form of a remarkable waterlogged and charred textile bundle found lying on a length of burned timber. Cleaned and painstakingly teased apart, this proved to consist of embroidered linen and silk originally decorated with stylised birds, lions, acanthus leaves, clusters of berries or grapes, and inhabited vine-scrolls. Textile experts concluded that it had been a tunic, with a decorated hem some 80mm in depth, and a belt loop with eyelets for a tape or ribbon. Strikingly, the textile lacks the decorative motifs expected of Insular art: instead of interlace, we have animals more readily associated with Classical and Byzantine art, though not the expected Christian symbols of fish, lamb, and crucifix that are more commonly found within this latter tradition.
Considering all the parallels, Mark Redknap concluded that the tunic was probably a diplomatic gift from the royal court of Wessex. From Chapter 80 of Asser’s Life of King Alfred (AD 893), we learn that various Welsh kings had submitted to Alfred’s dominion so that ‘they might enjoy rule and protection from him’ against ‘the violence and tyranny of the Ealdorman and of the Mercians’ and the threat from the dynasty of Gwynedd. Alfred welcomed such overtures and, when Anarawd ap Rhodri came to the Wessex court in person, ‘the king received him with honour, adopted him as his son by confirmation from the bishop’s hand, and bestowed many gifts upon him’. We are told that Tewdwr ap Elise, the king of Brycheiniog, was another of those who, ‘of his own accord’, sought the lordship of Alfred, and it is quite likely that the tunic was given as a diplomatic gift on that occasion, the motifs reflecting the Continent-facing culture of Alfred’s court by means of which these Byzantine designs might have been absorbed.

A logboat on the lake
One of the most interesting finds from Llangorse Crannog is the logboat, which is unusual for being relatively intact. Mortimer Wheeler, then Director of the National Museum of Wales, was informed promptly of the discovery and was able to inspect and record it before any significant shrinkage or deterioration took place. Radiocarbon dating by Roy Switsur, published by Sean McGrail in 1978, came out very close to the dendrochronological (tree-ring-based) dates for the crannog’s timber piles, so the logboat and crannog are judged to be contemporary.
In Episode 4 of the very first series of Time Team (available to view on All 4: http://www.channel4.com/programmes/time-team/episode-guide/series-1), Damian Goodburn supervised the construction of a replica, albeit that the need to complete the project within the programme’s traditional three days (here, 16-18 September 1993) meant that power tools were used alongside more authentic implements – a chainsaw for felling the tree and for removing the bulk of the waste wood, and a lorry for delivering the tree to the lake. Performance trials on the lake demonstrated that, even in its green and waterlogged state, the boat was easy to launch, paddle, steer, and beach, and that it was able to carry one person and a small load in calm water.

The reconstruction was subsequently submerged for storage, and when it was lifted in July 2016 the boat was found to be in a generally sound condition, though air-drying over the next three weeks led to some cracks appearing that had to be made watertight using moss and sheep’s wool dipped in molten beeswax. The loss of about a third of its weight as a result of drying made the boat very stable, well-suited for use on a shallow lake, especially for navigating through reed beds, and capable of some surprising speeds on open water – 2.5-3mph with a single paddler and 4-5mph with two. The original boat would probably have been able to carry four adults, or one person and a cargo.
During the 1990 excavations, fragments of a second punt-like logboat were discovered, and tree-ring analysis gave this a felling date of later than AD 1209. This placed the boat in the period when the lake was being used as a monastic fishery by Brecon Priory. Two decades earlier, in 1188, Giraldus Cambrensis (Gerald of Wales, 1143-1223), Archdeacon of Brecon, visited ‘Brecknock Mere’ (Llangorse Lake) and recorded his impressions. He tells us that the lake was rich in ‘pike, perch, excellent trout, tench, and mud-loving eels’, and that local people say that buildings, gardens, and orchards sometimes appear in the lake – such folklore might have been based on observation of the timbers of the crannog and memories of the time when the crannog served as a royal residence.

Armed occupation, operas, and origin myths
After the Dissolution, Brecon Priory’s estate was split between a number of local families, and this led to a long and complicated court case concerning the fishing rights at Llangorse. Hugh Powell, owner of land on the south side of the lake, was accused of stealing eels by Blanche Parry, Chief Gentlewoman of Queen Elizabeth I’s Most Honourable Privy Chamber and Keeper of Her Majesty’s Jewels (1507/1508-1590; see CA 357 for more about Blanche Parry, and a remarkable textile associated with her). The dispute continued after Parry sold her interest in the land to Powell, at which point another neighbour, the courtier (and later MP for Breconshire) Robert Knollys, claimed that Parry had no legal right to the fishing.
The dispute escalated when Powell and his supporters occupied ‘the tumpe in the said mere’, which he fortified and fenced, having landed armed men. Knollys responded by arranging for a boat to be transported in a cart drawn by a dozen oxen from the River Wye to the lake – a distance of 7 miles. He and his armed supporters were planning to attack the lake, but the authorities intervened: the case was heard in court and Knollys eventually gave up his claims, but the armed occupation of the crannog might well explain the post-medieval artefacts recovered during the 1989-1994 excavations, including gun flints and stone shot.


Post-medieval objects recovered from the crannog and the surrounding lake bed speak of the rise of Romantic tourism in the late 18th century, and the use of the lake for boating, angling, and picnics. The early medieval palisade around the crannog shows evidence of mechanical damage caused by collisions with pleasure boats and, more recently, by outboard motors, adding to the problem of natural wind and wave erosion and the drying effect of fluctuating lake levels. To help arrest the erosion, Cadw has now protected the crannog with a partly submerged 4m-wide and 0.8m-high bank of stone laid on a layer of geotextile. Timber marker posts with signs attached protrude from the bank and warn boats to keep away while, within the bund, further protection has been given to the palisade posts by supporting them with more than 2,000 bags of sand and stone chippings.
The story of the crannog has since been told in a number of imaginative ways, including a novel (The Crannog, 2013) by Trevor Houghton and a community opera, called Ynys Gwydr/Island of Glass (2012), setting new words to music drawn from four of Handel’s works. With a cast made up of students, members of local businesses, children, hospital workers, the unemployed, teachers, carers, and the retired, the opera was premiered at Theatr Soar, Brecon, on 12 April 2013, and can be seen on YouTube (search for ‘Nigel Griffiths Island of Glass opera’).

Finally, what are we to make of the fact that this is the only crannog known from Wales, and that there are no crannogs in England, whereas Ireland has at least 1,200 and Scotland at least 570? These crannogs come in many different sizes, using different constructional techniques, and have been built at different times in the past 3,000 years. Cognate sites have recently been identified in the Hebrides and shown to be constructed in the Neolithic (see CA 325 and 354) though ‘classic’ artificial island sites in Ireland do seem to be overwhelmingly of early medieval date.

Llangorse most resembles the Irish crannogs of this later period, and its sophisticated construction shows that it was built by people with the relevant skills and knowledge. Origin myths attributing Irish ancestry to rulers in some parts of Wales – including Brychan, legendary founder of the kingdom of Brycheiniog – are reinforced by the evidence of high-status Irish people in Wales in the form of ogham-inscribed stones and Irish personal names. There are also strong stylistic affinities between some Irish and Welsh carved stones and jewellery. The problem is that the ogham stones are earlier (5th and 6th centuries) and the earliest accounts of Brychan are later (11th and 12th centuries) than Llangorse. So we will just have to accept that there is no direct evidence linking the crannog to Irish settlers in Wales, but that needn’t stop us from using our imagination.
Further reading
Alan Lane and Mark Redknap, Llangorse Crannog: the excavation of an early medieval royal site in the kingdom of Brycheiniog, Oxbow, £40, ISBN 978-1789253061.