Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- available by post and through good bookshops everywhere. Bad bookshops might not have it....
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Saturday 2 December 2023

Did the Pembrokeshire hillforts have "round house" villages?

I have written many times,  in the past, about the Pembrokeshire hillforts including Foel Drygarn, Carn Alw, Carningli, Garn Fawr and Garnffoi.  But the other day I watched a National Park video which had a message that I think was thoroughly misleading -- namely that the settlement on top of Foel Drygarn was made up of lovely round houses such as those which have been reconstructed at Castell Henllys.  It was all explained in great detail, and with great conviction, by NPA resident archaeologist Tomos Jones and a colleague.  Wattle and daub and thick thatch figured prominently......

But wait a minute.  How much serious thought has gone into this nice easy explanation?  For a start, here is the Coflein extract:

From the Coflein record:

The most striking characteristic of Foel Trigarn is its pock-marked interior, the sites of at least 227 levelled house platforms where Iron Age houses once stood. There are also fainter traces of a further 42 uncertain platforms bringing the total closer to 270 house sites. It is highly unlikely that all these house sites were occupied at the same time. The entire hillfort was probably occupied and expanded over many centuries, rather than being used by a single leader or group of people. We are effectively seeing the remains of a complex and long-lasting prehistoric village, with all its phases of occupation on show. Early excavations in 1899 by S Baring Gould unearthed Iron Age and Roman pottery and artefacts which included spindle-whorls, fine glass beads and a jet ring from some of the house platforms. Sling stones were also found "in great numbers - some in piles.. (Baring Gould et. al., 1900, 210). A new survey by the Royal Commission and researchers from Portsmouth Polytechnic (in 1988) provided the first detailed plan.

There is no mention here of 270 big round houses with conical thatched roofs. There is mention of many phases of occupation -- and I reckon that at any one time less than 100 of the "hut circles" were in use -- with many of them being used as storage and animal shelters rather than as human dwellings.  The "hut circles" are for the most part either little platforms created by hollowing out and levelling the hillside or hollows with raised edges.  These rims are for the most part quite low -- less than 1 m high.  Maybe at one time they were higher, but I doubt very much that they were made of wattle and daub.  They are made of excavated stone fragments and rubble.  Maybe some of the material came from the local quarries which I have written about in previous posts.

We have to think about raw materials.  For a single straw hut like the ones at Castell Henllys you need vast quantities of either long-straw cereal crops or reeds from reedbeds.  In my estimation the people of Foel Drygarn had neither.  They may have had nettles, honeysuckle and brambles for the tying up of bundles and for lashing timbers together, but the nearest reedbeds were probably in the Teifi estuary of the Nevern Estuary, and the bleak environment op on Mynydd Preseli was probably no good at all for the growing of cereal crops.  If there were cereals, they were probably varieties resistant to the wind -- which meant short stalks.    The inhabitants also needed cow dung, clay, and chopped straw if they were to build wattle and daub walls -- and again I suspect they had a shortage of all of these.  

Size is another issue.  Almost all of the hut circles or platforms have diameters less than 6m -- and this is smaller than the optimal size for a round house with a self-supporting conical roof.  There may have been plenty of timber down below the mountain, but there was a practical limit on the dimensions of the branches that could be hauled up to the top.  A cost / benefit ratio applied...

And finally there is the matter of location.  I do not think that thatched conical roofs would have made any sense at all up here on the mountain summit -- a place of constant wind and frequent horizontal rain.   Huts of the type reconstructed at Castell Henllys (and at many other "Iron Age village" sites through the UK) are fine in the balmy lowlands, but just would not have survived up here.  

So I suspect that the buildings were not huts with conical thatched roofs at all, but rather small and primitive shelters with stone walls (maybe with moss or grass used to stuff the gaps and keep out the draught).  The roofs were probably low domes, made with a lattice of crossing branches and maybe with one or two internal supporting pillars.  Animal skins, birch bark and turf were probably the materials used for the roof.

I also think that the "village" on the top of Foel Drygarn was not permanently occupied.  Rather, it was a seasonal summer settlement, evacuated during the winter part of the year, when the villagers probably moved down into the lowlands, and enjoyed the shelter of the forest......

So there we are then.

Friday 1 December 2023

Wogan Cavern, Pembroke -- what happened during the LGM?

Some interesting things are coming out of the excavations in Wogan Cavern, under Pembroke Castle.  There is much interest in the site, and it has been featured on the telly for good measure.  Latest info here:

In a previous article in this journal (Dinnis et al., 2022), we described the first season of archaeological excavations at Wogan Cavern (Pembroke, southwest Wales). Although based on excavation of a very small volume of deposits, we suggested that the sediments in Wogan Cavern may have very good potential for preserving archaeological remains. Specifically, an intact early Holocene archaeological layer and underlying, bone-bearing Pleistocene deposits encouraged us to believe that the cave might be an important early prehistoric site. Here, we provide an update on our previous work, detailing the findings of the 2022 excavation season. The 2022 work identified several phases of historic and prehistoric activity. The early Holocene archaeological layer containing diagnostic Mesolithic artefacts, found previously in the eastern part of the cave, was shown to extend towards the centre of the cave. Stratigraphically lower deposits dating to the Pleistocene, previously demonstrated close to the cave’s eastern wall, were also shown to extend towards the cave’s centre. Excavation of the Pleistocene deposits close to the cave’s eastern wall revealed evidence for human occupation, with one and possibly two Upper Palaeolithic layers present. The archaeological assemblage(s) from these lower deposits bear similarities to the Palaeolithic stone tool assemblage from the famous Paviland Cave, located c.30 miles (c.50km) to the east. Overall, our 2022 work confirms that Wogan Cavern is an early prehistoric site of national, and potentially international, significance.


Over the years I have done many posts on the bone caves of SW Britain, including Paviland (Goats Hole), Daylight Rock, Eel Point, Hoyles Mouth, Coygan, Pontnewydd, Ffynnon Beuno etc.  Many years ago I even did some research with Mel Davies and Brother James at Ogof yr Ychen, and we did some radiocarbon dating.

What intrigues me is the existence of human and animal remains which clearly pre-date the LGM in many of the caves -- which means that the caves survived (at least once) deep submergence beneath active glacier ice and then the ice wastage phase that followed, without filling up with sediments.  Not only that, but the sediments associated with the bone finds are often very subtle and difficult to interpret.  

If we can tie in the occupation dates for the caves into the glaciation sequence, we will have progress.  But there is a major problem with the radiocarbon and other dating -- as we all know, new radiocarbon dates tend to give wildly different dates to materials as compared with the dates from 20 years ago.  This is down to more sophisticated technology and to advances in the understanding of correction factors.   So the "Red Lady of Paviland" is now though to have a date of around 33,000 yrs BP, whereas until quite recently the date was assumed to be around 23,000 yrs BP.

So people were using the Goat Hole cave prior to the Late Devensian climatic deterioration and the  arrival of the LGM ice after 30,000 BP, when they died out or moved southwards into areas where tundra hunting could be continued.  Then as the ice melted they moved north again.

But it's quite a challenge to bring the archaeological evidence and the glacial geomorphology evidence together, in the creation of a coherent story.  We aren't there yet, but we are working on it......

Ffynnon Beuno cave in Denbighshire -- sealed by Devensian ice and then released again.....

Ice edge retreat across West Wales, according to the BRITICE chronology.  How do these phases tie in with the independent data from cave research?

See also:
A Mid-Upper Palaeolithic human humerus from Eel Point, South Wales, UK 
Rick J Schulting, Erik Trinkaus, Tom Higham, Robert Hedges, Michael Richards, Bernice Cardy. 
Journal of Human Evolution, 2005

Most of the key Palaeolithic sites are shown on this map -- most caves were occupied for the first time after the LGM ice melted away, but some sites were occupied prior to the LGM


Brian John. 2023. Was there a Late Devensian ice-free corridor in Pembrokeshire? Quaternary Newsletter 158, pp 5-16.


PS  Rob Dinnis confirms that they will be back for more excavations next year, which is good news. He also confirms that there is good evidence of pre-LGM occupation at Wogan Cavern, in Priory Farm Cave and also at Hoyles Mouth near Tenby.

Thursday 30 November 2023

The big BRITICE model is more accurate than the ground "truthing".........

I have been looking again at the gigantic multi-authored paper that rounded off the work of the BRITICE team about a year ago.  Great work!  Reference:

Growth and retreat of the last British–Irish Ice Sheet, 31 000 to 15 000 years ago: the BRITICE-CHRONO reconstruction.  Chris D. Clark et al, Boreas Volume 51, Issue 4, October 2022, pp 699-758
First published: 07 September 2022

I wanted to check it again, because I recalled that the authors had all sorts of problems in reconciling the models of "maximum Devensian glaciation" (the LGM) around 26,000 years ago with the evidence on the ground. In several places in the text they express their frustration at the mismatch, and I now realise that the problems lay not with the computer modelling but with the unreliable field data contained within the published studies on which they had to depend.  (They did relatively little new fieldwork in the Bristol Channel and South Wales, so that did not help either......)

If we look at this map we see the predicted maximum and minimum ice front positions at the LGM. Quote: "The empirical ice-sheet reconstruction at 26 thousand years ago. The optimum ice limits (white with blue boundary) represent the favoured interpretation of the underlying data incorporating all geological, geomorphological and glaciological soft knowledge. From these optimum positions, limits were advanced and shrunk as far they could go without contradicting an age constraint to build the maximum and minimum ice limits (see inset key). These define the uncertainty around the optimum position, with the true ice limit likely to lie within this zone. Note that changes in palaeotopography and coastline position are also reconstructed."

The problem with the Bristol Channel and South Wales segment of the map is that they have (I think) fed into the computer model all sorts of data that are unreliable.  I suspect that they have told the computer that there are no traces of Devensian glaciation on the coasts of Devon and Cornwall, that Lundy Island was not glaciated at the time, and that there was a strange ice-free enclave in mid and south Pembrokeshire.  My article about the latter came out too late for the BRITICE work, but my suggestion that the "enclave" did not exist appears to have been accepted by everybody working in the field -- at least, nobody has challenged either my field evidence or my conclusions!  

As suggested in my article, I am quite convinced that there are good grounds for supposing that:

(1) Lundy was completely covered by ice during the LGM
(2) the whole of Pembrokeshire was submerged beneath LGM ice, as was the whole of Gower
(3) Devensian ice from the west reached the edge of the Vale of Glamorgan, but may not have covered it completely
(4)  some of the traces of glaciation on the north coast of Devon and Cornwall may well have been left by the LGM ice of the Irish Sea Ice stream

If these suggestions are accepted by the BRITICE authors, then the modelling of the British and Irish Ice Sheet becomes a great deal easier and more realistic.  If we add the necessity of modelling the southernmost ice edge even further to the south, on the edge of the Celtic Sea continental shelf, in accordance with collected field data (published in assorted papers by James Scourse and others) we have to model for minimal ice surface gradients and lateral ice spreading.  As I have argued on this blog many times, you cannot have a narrow ice lobe pushing all the way to the shelf edge in the middle of the Celtic Sea because there is no deep channel to constrain it and no flanking uplands -- so ice MUST have spread laterally (eastwards) at least as far as the Devon and Cornwall coast and well into the Bristol Channel.  It all makes sense........

This is the map showing modelled ice velocity, showing an ice flow velocity of c 1 km per year immediately adjacent to an "ice free enclave" in Pembrokeshire.  This is nonsense.  No wonder the modellers said that they were thoroughly confused!

This (below) is the ice flow / ice edge scenario that best represents what happened around the LGM of c 26,000 yrs BP.  It is based pretty solidly on field evidence as published in the literature.

If the BRITICE modellers had used this map as part of their "ground truthing" exercise and had fed it into their magical computer, then everything would have matched up very nicely and everything would have looked more realistic.........

Brian John. 2023. Was there a Late Devensian ice-free corridor in Pembrokeshire? Quaternary Newsletter 158, pp 5-16.

Anyway, let's see what the next generation of Devensian models looks like.  I'm still waiting for some sensible modelling of the Wolstonian and Anglian glaciations; that's when we will start to see some serious guidance as to the likely course of events in the saga of the bluestones.

Tuesday 28 November 2023

Bluestone "declassification" -- have the geologists lost the plot?

Not long ago I took the geologists to task for suggesting that the Altar Stone should be "declassified" as a bluestone because they now think it might not have come from Wales.  This is the ultimate manufactured absurdity -- maybe designed to divert attention from all the things they have got wrong over the past decade.  

The term "bluestone" is daft enough as it is, but it is just about acceptable if it is used as a shorthand label for "any stone at Stonehenge that is not a locally collected sarsen stone."  For years Ixer and Bevins have been trying to redefine the term to mean "any non-sarsen MONOLITH at Stonehenge" while getting into a frightful tangle by talking about multiple bluestone fragments that cannot be shown to have come from any monolith since there are no known close geological matches.  So imaginary or fantasy monoliths are included as bluestones as well. At the same time, they very conveniently ignore any "inconvenient" fragments of rock found at Stonehenge that do not fit into any of their designated "geological types" that are in themselves artifices. As I have said many times before, that is illogical and unscientific.  Nobody knows how many rock types there are at Stonehenge, and to some degree it depends whether you are a lumper or a splitter, but we would probably all agree that there are far more than a dozen.  Just read the literature since 1991 to confirm that........

We are never going to sort out what happened at Stonehenge unless we evaluate ALL of the foreign material at Stonehenge and try to work out how it got there.  And that includes assessments of packing stones, mauls, hammerstones, boulders (like the Newall Boulder), cobbles, axes and knock-offs, fragments and flakes.  It's intellectually lazy to simply assign all the inconvenient bits and pieces to a category called "adventitious".

Now, in this latest bizarre twist, Ixer and Bevins seem to want to assign to themselves the authority to determine what is a bluestone and what is not -- and have decided that you cannot refer to something as a bluestone unless it has come from the area within and around Mynydd Preseli.  

It's all a mess, and they know it.  

I had hoped that the ides of "bluestone declassification" was a mementary aberration, and that the geologists would promptly forget about it. But now up pops another publication, with the involvement of another team of geologists.  Quote:

"The Altar Stone is a grey-green micaceous sandstone, otherwise known as Stone 80. It is anomalous in its composition, size and weight when compared to the other bluestones. A very recent publication by a team of geologists, which included Prof. Bevins and Prof. Andò, proposes that the Altar Stone be declassified as a bluestone. Based on X-ray and Raman analysis in the laboratory on fragments of the stone using a Renishaw inVia Raman microscope, they hypothesise that the stone did not originate from the Anglo-Welsh Basin, as previously thought. Instead, there is strong correlation between the Altar Stone and sandstones in northern England or Scotland."

So it looks as if the "declassification of inconvenient Stonehenge bluestones" is going to be pushed as the next great Stonehenge debate, led by the heroic team of geologists who like to refer to themselves as "the pet rock boys".  It's even more ridiculous and sterile than some of the debates that have gone on in glacial geomorphology in the past, relating to the labelling of lithological units.   Don't get me going again on the "Penfro Till Formation" (invented by Prof David Bowen) which does not actually seem to exist, or on the labelling of certain other deposits in the glacial sequence of Southern Britain......

Friday 24 November 2023

The Saga of Breakheart Bottom

Breakheart Bottom, near Imber

Once upon a time an ice giant with frozen fingers travelled from the far west, where he lived close to the setting sun, to visit a cousin of his who lived on the chalklands close to the place where the sun rises.  He was called Dafydd and his cousin was called Cuthbert.  Anyway, Dafydd carried with him  a bag of pretty pebbles as a gift for his host, because that is the way with giants. (He thought they were pebbles, because he was a giant, but for ordinary people they were HUGE......)  When he arrived he was welcomed with open arms by his cousin, who lived in a warm and pleasant valley with not many trees.  He just loved his gift from the west, and the two giants arranged the pebbles in a nice pile where they could be admired by all who travelled that way.    They passed the time pleasantly enough, talking of other giants and the latest happenings here and there.  But then Dafydd began to feel uncomfortable because his fingers started to thaw, and he was much happier when they were frozen.  So at last he took his leave and headed back to the icy lands of the west.  Cuthbert was very proud of his collection of pebbles, but he was not very intelligent and not very attentive, and when he was out wandering one day a gang of human beings came and stole the pebbles because they wanted to arrange them in a pretty pattern to show to their friends.  They left one behind because they were in a bit of a hurry, but a human being who lived nearby (Mr Bole was his name) stole that one and buried it in the middle of a mound in his garden.  Cuthbert was distraught for a while, but soon forgot about the pebbles, because he had other pressing matters to deal with.  But after the passage of a few centuries Dafydd came on another visit, but without any pebbles this time because he was feeling his age, and anyway, pebbles had gone out of fashion.  He was welcomed warmly enough by Cuthbert, but he immediately noticed that the nice pile of pebbles had gone.  Cuthbert explained that they had been stolen by some humans, but poor Dafydd was distraught because his cousin had not looked after the pebbles better, and because of the evil ways of human beings. He broke down and wept giant tears, and ever since then the pleasant valley where Cuthbert lived has been called Breakheart Bottom...............

So there we are then.

Even if the above folk tale is not necessarily true, I am intrigued by the manner in which both Aubrey Burl and Geoff Kellaway homed in on the area around Chitterne, Heytesbury, Boles Barrow and Imber as the possible area in which the Stonehenge bluestones were deposited by ice and from which they were collected up by our heroic ancestors.  Breakheart Bottom is in the middle of that area, and around half of the territory on the map below is within the MOD firing range.  

I just wonder whether this is the area in which the truth resides, just waiting to be uncovered?

Tuesday 21 November 2023

Stonehenge in its Landscape -- free online

I have just caught up with the fact that the big (definitive?) volume edited by Ros Cleal et al is now online as a free PDF, available for download. So well done, EH and the Archaeology Data Service.

I refer to it frequently, and I really do like its cool, matter-of-fact approach in which evidence is presented methodically, analysed and assessed as to its importance -- all mercifully free from the hype and hubris that we see all too often in Stonehenge studies........

It's not perfect -- no book ever is -- but since it was published in 1995 nothing has come near it in terms of value for money.  And now it's free!  Enjoy........


This volume represents a detailed discussion of the structural history of Stonehenge, arrived at by the integration of evidence from primary records of excavations carried out between 1901 and 1964. These major campaigns of excavation and recording include those of Prof William Gowland (1901); Lt-Col William Hawley (1919-26); Profs Stuart Piggott and Richard Atkinson with J F Stone (1950, 53-5,56,58 and 64) and some smaller, previously unpublished campaigns as well as more recent, small-scale excavations which are already published. The evidence for the use of the monument from the Middle Neolithic to the present day is discussed in terms of its landscape and social settings. The evidence for the rephasing of the monument, including artefactual and ecofactual assemblages, details of the radiocarbon dating programme, geophysical surveys, transcripts of all available field plans, sections, and stone elevations is presented together with a variety of summary lists, concordances, and a guide to the site archive. A new suite of radiocarbon determinations has been obtained which redefines our understanding of the sequence of construction and use of the monument and augments the surviving archaeological evidence.

Saturday 18 November 2023

The gullibility of the innocent.........


This image is doing the round in social media, on assorted nutty archaeology sites and Facebook pages galore.  Almost everywhere it is accompanied by serious discussions about how this mammoth was entombed in crystal clear ice and so on and so on.  It's all complete rubbish, of course.  The accompanying text was about the discovery of a baby mammoth in the permafrost  -- that's an old story anyway, now recycled -- and all regurgitated by people who skim science stories in learned journals, extract the spectacular bits and seriously misrepresent almost everything because of the obsesssion with "impact."  To hell with ethics.  The image has been created by somebody having fun with AI technology, which is contributing -- faster than any of us thought possible -- to the death of science.  It's now almost impossible to separate out the real images from the manufactured ones....... 

In reality, the remains of mammoths found in the permafrost are always scruffy, squashed and very dirty.  Permafrost ice does not look like crystal clear glacier ice or lake ice.  And when animals die in Arctic bogs they do tend to fall over in the process.....

Sounds familiar?  For years we have had nonsense press releases flagging up the wonders of Neolithic quarries, lost stone circles and heroic stone transport expeditions, and as we speak people are probably working on "photographs" of precisely what is supposed to have been going on.

Here is my contribution.  This, by the way, is a real, undoctored photo from Antarctica.

Breaking news!  Just discovered in Antarctica -- a pyramid which is far larger than the Great Pyramid of Giza, and next to it a smaller pyramid is just emerging from the melting ice cap.  This proves that Ancient Egyptians discovered Antarctica and developed an advanced civilisation, well before the start of the Ice Age.  This of course transforms our understanding of the ancient world, and the history of the world must now be re-written.