Stonehenge and the ring of truth
Anyone with even a passing interest in the history of west Wales will be aware of the links between the Preseli Hills and Stonehenge, the giant Stone Age monument that dominates both the Salisbury Plain of southern England and the entire history of the British Isles.
For more than a century it has been acknowledged that the so-called bluestones - spotted dolerites - of Stonehenge were originally quarried from rocky outcrops in the north Pembrokeshire hills around 5,000 years ago.
That discovery has left archaeologists and historians questioning why ancient builders would have gone to the trouble of transporting so many giant stones, each weighing between 1.2 and three tonnes, some 200 miles across the pre-historic British landscape. The question is all the more perplexing because Stonehenge’s giant sarsen stones were quarried within a few miles of iconic monument.
What then could be the relevance of the Preseli bluestones?
Writing almost 900 years ago in aroud 1136, the monk Geoffrey of Monmouth claimed that Stonehenge was built from an already ancient stone circle located in the far west of Britain or Ireland. According to Geoffrey, the wizard Merlin had magically transported the stones to Salisbury as the spoils of war. The story, much like the rest of the tales of Merlin and King Arthur, was fantastical and absurd, and ignored by all serious Stonehenge theorists.
The questioned remained though: why were those stones transported all the way from west Wales to Wiltshire. The only plausible answer was that the stones were considered somehow unique by the builders of Stonehenge, but what made them so special?
Now, archaeologist Mike Parker Pearson, professor of British Prehistory at University College London, has unearthed the true story of the bluestones and in so doing has rewritten the history of both Stonehenge and the British Isles.
“I’ve been researching Stonehenge for 20 years now and this really is the most exciting thing we’ve ever found,” said Mike.
Even when he began working at Stonehenge it had long been accepted that the current configuration was not the original and the layout had changed a number of times in the long distant past.
“We know that the current layout dates to around 2,500BC but the original configuration dates to 3,000BC,” he explained.
“We always thought that the original Stonehenge was just a monument made of earth – a ditch and bank, but we discovered that in fact it had always been a stone monument.
Mike’s excavations revealed that the original Stonehenge circle was much larger than the current monument, some 110 metres in diameter – and made up solely of Preseli bluestones.
“This was a major surprise,” he said.
Further revelations came when Mike was joined at his Stonehenge excavations by a Malagasy colleague he had worked with on previous digs in Madagascar.
“While we were chatting one day, he made the casual observation that Stonehenge was a place built to honour the ancestors. He said that in the Malagasy culture, stones represent the ancestors,” he said.
“We already knew that Stonehenge is the largest Neolithic burial site in Britain and so if he was right that the stones represented the builders’ ancestors then it makes sense that their place of origin really matters.
“It became clear that to understand Stonehenge, the secret is in the bluestones.”
So Mike and his team began to consider the possible reasons for transporting the stones more than 160 miles.
“It made us think “Good heavens, there must be something really important in the Preseli area”. That’s what started the whole journey. What my friend said gave me a hypothesis to test.”
Mike realised that it was not enough to accept that the bluestones had come from the Preseli Hills, but he needed to identify the specific outcrop of rock where they had been quarried.
“I wanted to find out exactly where they came from and why,” he said.
By analysing the outcrops and the Stonehenge bluestones, geologist Professor Richard Bevins, based at the National Museum of Wales, was able to locate the exact Stone Age quarries that produced the stones, and in so doing, shifted their point of origin from the traditionally accepted southern slopes of the Preselis to outcrops further north.
This discovery would prove fundamental to Mike’s theory.
“In 2010, Richard was able to pinpoint one of the outcrops that had been the source of the bluestones at Craig Rhos y Felin,” said Mike. “It proved that up until then, archaeologists had been looking at the wrong outcrops.”
For the next five years, Mike and his team excavated Craig Rhos y Felin – and another outcrop at nearby Carn Goedog, which also showed the unique geological “fingerprints” found in Stonehenge bluestones.
“We discovered that the quarry at Carn Goedog, even in the Neolithic age, was being operated on an industrial scale, and we were able to show that it is the original site for the majority of the bluestones at Stonehenge.
“At both sites we found the facilities – levers, pivot points and a specially constructed platform and loading bay – to both quarry the stone and enable them to be taken from the site. We even found a sledge route leading out of the quarry at Carn Goedog and away down to a dry riverbed.
“The other great moment was finding the tools they had used. We had thought it would be hammerstones, but actually the main tools they were using were wedges – it was blinding obvious once we had found them, but we’d never really considered it before.
“We have even found the marks where they were jammed into the fissures in the rock.”
But the truly amazing discovery was still to come.
The remnants of a handful of charred hazelnut shells – presumably tossed into the fire while a Stone Age quarryman ate his lunch – has enabled Mike and his team to completely rewrite history.
“We were able to carbon date the hazelnuts,” explained Mike, “and they told us that the stones at Carn Goedog were quarried around 3,400BC – more than 400 years before the first monument was built at Stonehenge.
“The thinking had always been that the stones had been taken straight to Stonehenge after quarrying, but that had always seemed to me to be unlikely – why would they want to quarry stones from a very particular outcrop on a specific hill in the west of Wales just to take them all the way to build Stonehenge. It just didn’t add up.
“Once we had those new dates, everything began to fall into place.
“It seemed far more likely that the stones had already been erected into a circle and it was that circle itself that was taken. It meant that it was the circle rather than the stones that was the important thing.”
Although Mike had previously considered the possibility of there being an earlier stone circle somewhere in the Preseli Hills, the theory had been suggested and dismissed almost a century earlier.
“I can’t claim credit for the idea,” said Mike. “It was first proposed by the Welsh archaeologist Herbert Thomas in 1923 – he described it as a venerated stone circle, but the theory had been just about forgotten.”
The problem, Mike explained, was the stones.
“People were too busy thinking about the stones – there were all sorts of theories about why they might have been so special: some people thought that maybe the spots in the dolerites were like the stars in the night sky; another was that the unique geology of the stones meant that if you tapped them in a certain way it made a specific noise and the stones were some kind of giant musical instrument.
“All the emphasis was being placed on the fact the stones were these spotted dolerites. Everyone thought it was the stones that were moved rather than an actual stone circle.
“Everybody was thinking about it the wrong way round and had forgotten the words of Herbert Thomas.”
And so, after searching for a needle in a haystack to find the actual quarries, Mike led his team on an even more impossible quest: to find an ancient stone circle that had not existed for more than five millennia.
“What we were looking for were the holes in the ground left after a stone was removed 5,000 years ago,” said dig supervisor Dave Shaw, summing up the team’s predicament on the BBC documentary Stonehenge: The Lost Circle Revealed.
Even Mike thought the challenge would be too much.
“For a long time I thought ‘what are the chances of finding it?’” admitted Mike.
However, thanks to cutting-edge science, the team was able to draw up with a list of potential sites all within a few miles of the quarries.
“There were lots of interesting circular monuments that had never been investigated and we realised that we had to work through them one at a time,” said Mike. “Each of them looked really promising to begin with.”
That early promise began to evaporate as one by one the sites were excavated and eliminated.
“Although it was disappointing, we did manage to flesh out the history and archaeology of Preseli. It is a wonderful place with a rich history.”
Mike’s team unearthed Bronze and Iron Age forts plus a wealth of other surprising discoveries.
“We even found a previously unknown Roman villa,” he laughed.
Despite the incredible finds they were making, the original home of Stonehenge managed to evade them.
“It was tremendous archaeology,” said Dave, “but it wasn’t what we were looking for.”
With time and options running out, they were left with one last possibility.
Waun Mawn had been flagged as a potential site in the early days of the investigation thanks to four bluestones similar to those at Stonehenge remaining in situ, although only one remains standing. However, geophysical and magnetic surveys had shown nothing to indicate any additional workings and the site had been dismissed.
“We turned to Waun Mawn as we had nowhere else left to go,” said Mike. “It’s a wild place and excavating up there was going to be far from easy.”
Nevertheless, Dave and his team of diggers began work on the rain-lashed, wind-swept peak.
Much to everyone’s surprise they unearthed what appeared to be ancient stone hole in the ground, long since filled in by the passing of time. Then they found another and another and another until they revealed part of a circle made up of as many as 50 standing stones.
What proved all the more exciting was that the diameter of the circle was 110 metres – exactly the same as the original Stonehenge bluestone circle.
In an astounding meeting of modern techniques and traditional digging, one unusual pentagonal-shaped hole was excavated which matched exactly the shape and dimensions of one specific stone still standing at Stonehenge today.
Yet more science – measuring traces of ancient sunlight in the soil - confirmed that the stones had been placed at Waun Mawn in 3,300BC – exactly the time they had been extracted from the Carn Goedog quarry.
The layout of the stones also precisely matched the alignment of the rising sun on the winter and summer solstices at the time of the Preseli circle’s construction – as does Stonehenge.
The discoveries were conclusive.
Mike and his team had proved that the bluestones which were used to build the first Stonehenge had, for almost 500 years, stood as a giant stone circle monument in the Preseli Hills prior to it being dismantled and transported to Salisbury Plain.
“It has taken us a long time to get there, but we finally understand the true origin of Stonehenge and the importance of the bluestones,” said Mike.
“Stonehenge really does belong to Pembrokeshire after all.”