It is generally accepted that the appearance of Neolithic ‘things and practices’ – pottery manufacturing, distinctive stone tools, and farming – can be dated in Britain and Ireland to the 41st to 39th centuries BC. Much debate continues over the question of whether there were different regional start dates, and whether these represent a single migration into south-eastern England, followed by the dissemination outwards of Neolithic ideas by the descendants of a pioneer population (as proposed by the authors of Gathering Time, published in 2011 but now under revision; see CA 259), or whether there were multiple migrations from different parts of the near Continent (the alternative model championed by Alison Sheridan; see CA 290).

Even so, the general picture seems to be clear: the Neolithic is marked by the arrival of new populations from the European mainland, where farming was already well established, bringing with them domesticated species of animals and crops hitherto unknown in Britain and Ireland. And as they took in land for cultivation, they also invested in the construction of substantial monuments that continue to be a source of wonder and research some 6,000 years later.
Long cairns (consisting of stone-lined chambers covered in a mound of stone and earth) and long barrows (largely covered in earth) are among the earliest of these Neolithic monuments, and the distribution of these has led to the identification of a number of similar monuments known to archaeologists as the ‘Cotswold-Severn group’. They consist of large mounds, trapezoidal in shape, often with a forecourt and a false portal at the broad end, and covering a series of concealed stone-lined chambers that were either entered from the long sides of the cairn (lateral chambers) or from the forecourt (terminal chambers).

The Cotswold-Severn group contains a cluster of 14 monuments around the Black Mountains of south-east Wales on the western side of the River Severn, while on the eastern side are such well-known Cotswold monuments as Hazleton North and Belas Knap, as well as a small group on the North Wessex Downs, including Wayland’s Smithy and West Kennet Long Barrow. New examples continue to be found – the Sisters Long Barrow, near Cirencester, Gloucestershire, is currently being excavated by Tim Darvill and a team from Bournemouth University, while the Dorstone long barrows, in Herefordshire, were recently excavated by Julian Thomas, Keith Ray, and a team from the University of Manchester (see CA 285 and 321), and work continues at nearby Arthur’s Stone.

We have frustratingly few precise dates for these monuments, but in the concluding chapter of The First Stones, Alasdair Whittle, William (Bill) Britnell, and Seren Griffiths make a strong case for the long cairn at Penywyrlod as perhaps the earliest example of Neolithic monument-building in the Black Mountains region, and that its construction was ‘a signal part of the establishment of a Neolithic presence in inland south-east Wales’.
Contrary to past interpretations, they go on to argue that it is a strikingly novel long cairn, perhaps unprecedented in southern Britain, and that ‘it is not clear that any other laterally chambered monument with multiple chambers is any earlier’. If so, we are in for a major correction in our understanding of the Cotswold-Severn group. The idea that Cotswold cairns and barrows provided the model for those in the Black Mountains could be reversed, so that the Cotswold-Severn group might more accurately be characterised as the Severn-Cotswold group, giving primacy to at least one of the monuments on the western side of their distribution.
Long cairn composition

The long cairn at Penywyrlod (pronounced ‘Pen-er-whirl-odd’), located near Talgarth, in Powys, is one of the best-preserved of this class of monument. It was partially excavated in the 1970s, as were the remains of the much more fragmentary cairn at Gwernvale, on the western outskirts of Crickhowell. Bill Britnell returned to Penywyrlod in 2015-2016 to undertake geophysical survey and small-scale excavation in advance of much-needed conservation work by Cadw. This new intervention, combined with advances in archaeological methodology, have enabled these two monuments in particular, and long cairns in general, to be reassessed.

Bayesian statistical modelling has been used to refine the previously wide span of radiocarbon dates for these two monuments, and as a result it is now believed that Penywyrlod was built in the 38th century BC (3775-3720 cal BC at 68% probability). This makes it an early construction in the sequence, probably built within 130 years, or five generations, of the first Neolithic presence in the region. It is also one of the largest, measuring 53m (175ft) in length, narrowing from 22m (72ft) at the broader south-eastern end to 11m (36ft) at the north-western end.
The authors compare its dimensions to those of similar cairns in the Black Mountains cluster and observe that these vary greatly in length (from 27m/88ft upwards), but that the maximum widths are all closely similar. Penywyrlod also compares in length to similar long cairns in the Severn-Cotswold group, such as Hazleton North (56m/184ft; dated to the first half of the 37th century BC), Wayland’s Smithy (54m/177ft), Belas Knap (53m/175ft; possibly 37th century BC), and Ascott-under-Wychwood (49m/160ft; second half of the 38th century BC).

The Penywyrlod mound was built on a sloping land surface that is 5m (16ft) higher at the broader (portal) end than at the tail end. The overlying cairn material is 2.5m (8ft) high at the portal end, rising to 3m (10ft) towards the middle of the mound and falling to just 0.8m (30in) at the tail. Combined with the underlying slope, the cairn is thus considerably higher at the portal end, narrowing and diminishing towards the tail end – a sophisticated design that uses false perspective to exaggerate the appearance of the monument’s already considerable length.
At the portal end, the forecourt is flanked by two horns, 11m wide at the outer edge and narrowing to 1.5m (5ft) at the point at which it meets the two orthostats of the portal structure. One of these orthostats stands to a height of 2.1m (7ft), but the other has collapsed, together with the lintel that the uprights once supported. From this point, an outer revetment wall extends round the horns and along the flanks of the mound, neatly constructed from specially selected stones brought from some distance away (and to whose possible symbolism we will return).

The existence of the portal and forecourt suggests that it leads to the interior of the mound. In fact, the burial chambers are spaced out along its two long sides. Four certain chambers have been identified, and at least three others are suggested by anomalies detected by recent geophysical survey. The chambers consist of simple box-like structures formed by stone slabs, and these are connected to the outer revetment wall by passages of about 1.4m (5ft) in length. The internal measurements vary: the largest is about 4.2m by 1.4m and 1m in height (14ft by 5ft by 3ft), divided into two chambers. The chambers are independent of each other, but seem to form symmetrical pairs, entered from opposite sides of the cairn, and it is thought that the chambers diminish in height along the length of the cairn.
Deciphering the deceased
What were the chambers for? This is a real puzzle. The standard explanation is that they are burial chambers, designed to hold human remains. They rarely contain the complete articulated skeletons of one or more individuals, however. Instead, a typical assemblage might contain bones or fragments of bone from a number of individuals of different dates. This has led to the theory that the cairns were communal burial mounds into which bones were placed that had been selected to represent a cross-section of the community – males and females, children and adults, and some with life-changing injuries or disabling conditions.
An alternative theory is that the bones are those of the founding lineage and their direct descendants. This idea was given strength last year when the journal Nature published the results of aDNA analysis of the bones and teeth of 35 individuals whose remains were found at the Hazleton North long cairn (see CA 384). This showed that most of the people buried there came from five continuous generations of a single extended family. Some of us rushed to conclude that this meant that all long cairns were constructed as the tombs of socially significant individuals, but the Hazleton North cairn is relatively late in date (37th century BC), by which time burial practice might already have been changing to favour the members of a dominant lineage, reflecting the dynamics of the steadily increasing social stratification that developed some time after the initial establishment of early Neolithic land takes.

At Penywyrlod there is evidence of some degree of selectivity, with strong differences in the composition of human bone elements in the three adjacent chambers examined so far. One of the chambers (NE I) contained virtually nothing and might even have been deliberately emptied as part of a closure and abandonment process; in another (NE II) there was an emphasis on adult males; in a third (NE III) there were adults of both sexes, young and old; older and younger youths; children; and infants. The authors thus suggest that the monument may have represented a scattered regional population rather than a closely related family group as at Hazleton.
Michael Wysocki, author of the chapter on the human remains from Penywyrlod, concludes that the chambers served as ossuaries for human remains that had decayed elsewhere – perhaps laid to rest in a temporary grave and later disinterred. As well as representing differing numbers, balances of age and sex, and varying time spans, there is evidence of repeat visits and access to the chambers, and of the manipulation and rearrangement of the bones, many of which show signs of weathering and abrading.

Even more of a puzzle is the question of access to the chambers. The masonry of the outer revetment wall at Penywyrlod showed that sections of the wall had been removed and rebuilt on at least one occasion to provide access to the entrance passages within the cairn. It is possible that these entrances were marked in the revetment wall by a series of lintels. But anyone entering chamber NE II would have found access blocked by a substantial slab that looks as if it was put in place during the construction of the monument. This could imply that any human remains in the chamber must have been deposited as a single act, but the radiocarbon dates from the bones in one of the chambers show a long span of use, with a date range of between 170 and 490 years (at 95% probability), or 305 to 435 years (at 66% probability): in other words, these remains represent at least seven generations, and potentially twenty.
The authors of The First Stones characterise this as a ‘locked room mystery’. They consider various possibilities. Perhaps that there was a sufficient gap between the sealing stone and the chamber to allow bone fragments to be ‘posted’ into the ossuary; perhaps there might have been a porthole that enabled access to the cist; in theory the cairn might have remained unfinished to give access to the chambers for many decades; or the remains could have been deposited on a single occasion but included ancestral material. None of these is supported by the dating evidence or the mound’s constructional details, so it remains an open question, but it seems clear that if the passage could be entered, but not the chamber, there must have been a difference in symbolism between the uses of the passage and the cist, with the passage possibly serving as the focus for whatever rituals or procedures took place.

Lauding the local landscape
Long cairns as a whole, as well as in their component parts, would have had multiple meanings for those who built them, and the authors believe that the location of the monument, the orientation, the outlook, the shape, and the materials used in its construction all have significance. Visual associations appear to be important, and the distribution of tombs in the Black Mountains cluster suggests a strong association with the spectacular peaks of the northern, western, and south-western escarpments, while there are no tombs on the eastern side, with its less dramatic landscape. Arguably the very shape of the long cairns mimics the form of these conspicuous peaks, with the long shoulder and steep escarpment of such hills as Hay Bluff, Twmpa (Lord Hereford’s Knob), and Pen Allt-mawr mirrored by the precipitous portal and the long tail of Penywyrlod.
Then there are the materials from which Penywyrlod was constructed. Where a source can be identified, the slabs used to construct the chambers and orthostats are typical of the sandstones that underlie the site, but the outer revetment wall uses a distinctive pale greenish-grey to olive form of fine-grained sandstone typical of the Senni Formation that outcrops on the higher slopes of Mynydd Troed, the distinctive 609m-high peak that lies 2.5km to the south-east of Penywyrlod, and towards which the cairn is aligned. Strikingly, the dry-stone revetment wall is constructed of small slabs that mimic the finely bedded joints and fissures in the natural outcrops on Mynydd Troed from which the stone was probably quarried.

This association between tomb, geology, and dramatic landscape feature does not seem to be accidental, because to move even a short distance away from Penywyrlod is to lose the view. It is notable, say the authors, that Mynydd Troed, which dominates the skyline to the south-east, and even the more distant peaks of the Brecon Beacons to the south-west, disappear from view a matter of only tens of metres from the mound. In each case, the cairns in this group have wide-ranging views taking in near and distant hills, upland peaks, and a broad swathe of land. Clearly, there is a symbolic dimension to Penywyrlod that relates to the landscape and any mythological qualities that Neolithic people associated with it.

Such an association is not inconsistent with one of the dominant strands in the archaeological interpretation of such monuments, which is that they represent a landscape form of title deed that says ‘we were here first, and this home of our ancestors is the proof’. But this is a somewhat functionalist approach to the meaning of long cairns and there might be simpler ways of achieving the same effect, leaving aside the question of whether it would have deterred a determined intruder.
We also know that early Neolithic settlement in south-east Wales was dispersed and small-scale – recent excavation of sites along the route of the South Wales Gas Pipeline underlines the picture of generally scattered and small-scale occupation, and the environmental evidence shows a mainly wooded setting (see CA 216 and 376). The strontium and oxygen isotopic evidence presented by Samantha Neil in The First Stones shows that the majority of those whose teeth could be analysed from the tomb chambers had obtained their early life diets from elsewhere in the region, but perhaps not that far away. It looks as if there was plenty of opportunity for movement into and around the region in the 38th century BC.

By contrast, the people buried at the Ty Isaf cairn, 4.5km from Penywyrlod and built around a century later, had a local diet in childhood. Michael Richards’s analysis of the carbon, nitrogen, and sulphur isotopes in bone collagen (much of which reflects the diet in the last decade before death) argues that the differences could reflect the biological contrasts between earlier wooded landscapes and later, more open areas. In this light, the construction of Penywyrlod looks more like a statement of intent, marking the start of the process of taking in new land, rather than a claim that seeks to consolidate a hold on an already occupied and cleared location.
The ‘title deed’ interpretation misses the possibility, too, of more symbolic, spiritual, philosophical, or religious narratives, or the qualities of display, performance, emotion, and wonder inherent in the skilful construction on such a massive scale of a monument with fine outer walling, pleasing shape, and false linear perspective. The authors note that these monuments are located at the western limits of the long cairn distribution and that, further west, Neolithic communities were building dolmens at about the same time as Penywyrlod was under construction. Vicki Cummings and Colin Richards have argued that we should see dolmens as monuments designed to evoke awe and wonder (see CA 390). The same surely applies to long cairns which, like dolmens, seem designed to evoke in onlookers a recognition of some link between the human construction and the dramatic (and probably mythologised) local landscapes.
![above A view of Mynydd Troed (literally ‘Foot [-shaped] Mountain’) on the skyline, emphasising the similarity in the form of this natural landscape feature and the shape of the Penywyrlod long cairn.](https://i0.wp.com/the-past.com/wp-content/uploads/2023/01/post-1_image13.jpg?ssl=1)
The underlying message of The First Stones, expressed in Alasdair Whittle’s first chapter on how long cairns have been interpreted in the past, and picked up again in the concluding chapter, is that the archaeological cast of mind is overly concerned with typological similarities at the expense of differences. There are similar kinds of monument to Penywyrlod in Normandy, Brittany, and other parts of western France, but they date from up to 1,000 years earlier, and it is difficult to see these as a direct source of inspiration given the time gap. Instead, we should give credit to the human capacity for invention, the desire for novelty, and the striving to be different, which can be especially marked at times of significant change.
This is not entirely a new idea – anthropologists in the 1930s called it ‘schismogenesis’ – but it is an approach to archaeology that is definitely gaining renewed support in the 21st century, perhaps as a reflection of our own times, in which we emphasise diversity and distinctiveness in contrast to past tendencies to classify and generalise. This article has scarcely scratched the surface of the topic, which the authors explore in more detail with the individual histories of Gwernvale and several other long cairns in the Black Mountains group, but the moral of the story is clear: don’t assume that all tombs are the same. To understand them, we need to put them in their individual historical contexts, a process that has been greatly helped by the development of such precise dating as is now available through Bayesian analysis.
All images: William Britnell and Alasdair Whittle, unless otherwise specified
Further reading
William Britnell and Alasdair Whittle (eds) The First Stones: Penywyrlod, Gwernvale and the Black Mountains Neolithic Long Cairns of South-east Wales, Oxbow Books (ISBN 978-1789257397, £38).