Excavations in an ancient quarry in southwest Wales have so far yielded 15 sandstone wedges that were used to break off natural stone columns from the bedrock.
They also discovered V-shaped slots in two columns that had been earmarked for use – but never removed.
The archaeologists – led by Professor Mike Parker Pearson of University College London’s Institute of Archaeology – also found a number of hammer stones, potentially used to force in the wedges.
All the tools appear to have been made elsewhere from stones that could not have been found in or around the quarry itself.
Scientists know the Stonehenge early phase standing stones (known as “bluestones”, rather than the later more famous and much larger “sarsen” stones) come from this and other Pembrokeshire prehistoric quarries – because of chemical identification tests they have carried out on the rocks.
So far, only two quarries have been identified – both on the northern slopes of the Preseli Hills in Pembrokeshire, southwest Wales – but geologists, who have studied the Stonehenge bluestones, think it is likely there were at least three or four other quarries that have yet to be found.
The discovery of the tools is likely to rekindle one of archaeology’s biggest debates – how did the builders of Stonehenge transport the bluestones (an estimated 79 of them, each weighing approximately 2 tons) from southwest Wales to Salisbury Plain.
There are three major potential methods – by land, by land and river, and by sea and land and/or river.
The most practical way would have been predominantly by sea – but the most ritually, politically and ideologically impressive method would have been predominantly by land. Only very detailed future archaeological research will stand a chance of finding the route and cracking that particular mystery.
In the first, more maritime scenario, the stones would potentially have been moved by raft (or catamaran) down Pembrokeshire’s river Taf into the Bristol Channel and then along England’s river Avon to within 20 miles of the Salisbury Plain site earmarked for Stonehenge.
In the second scenario, the stones would have had to be carried by stretcher or hauled on sledges (or possibly rollers) for long distances over often extremely challenging terrain (with only limited opportunities for river transport).
This second method would certainly have had ostentatious political and ideological advantages – but it would have required vast amounts of manpower, time, effort and intertribal or interclan acquiescence.
The discovery of the stone quarrying tools, which date to the approximate time of the construction of the first stone phase of the monument (c 2900BC), proves beyond reasonable doubt for the first time that Neolithic people quarried the Welsh stones that ended up being used to build the world’s most famous prehistoric temple.
But why did the builders of Stonehenge want to get their standing stones from 175 miles away when they could have used perfectly good local stones from Salisbury Plain?
The answer is probably genealogical. Chemical signatures found in the bones of early Stonehenge people suggest many of those individuals were originally from western Britain, not from Salisbury Plain. It is therefore conceivable that the stones of early Stonehenge were brought to Salisbury Plain from the area associated with the builders’ ancestors.
Fascinatingly, in much later (medieval) Arthurian literature, the stones of Stonehenge are said to have been brought by the magician Merlin from the far west (although, in the legend, from Ireland, rather than southwest Wales).
The fact that the stones were brought from Pembrokeshire to Salisbury Plain raises another key mystery. If indeed they were transported to their new home as clan or tribal heirlooms, then it suggests they already possessed great significance. And that implies the possibility that they had already functioned as a ritual monument (ie as standing stones) in Wales, long before they were taken to Salisbury Plain.
So the big archaeological question is whether the initial stones of Stonehenge were second hand or freshly quarried for use so far away. If the former theory is correct, then the original Stonehenge was actually in Pembrokeshire – not in England. The hunt is therefore now on for the original site of this potential Welsh proto-Stonehenge.
Without doubt Salisbury Plain’s world-famous prehistoric temple still holds many secrets – but archaeological research over the coming years is likely to reveal them.
The discovery of the quarrying tools – published today in the British archaeological journal Antiquity – has been made by a team of archaeologists and geologists from UCL, Bournemouth University, the University of Southampton, the University of the Highlands and Islands and the National Museum of Wales.
Professor Pearson said: “What’s really exciting about these discoveries is that they take us a step closer to unlocking Stonehenge’s greatest mystery – why its stones came from so far away.
“Every other Neolithic monument in Europe was built of megaliths brought from no more than 10 miles away. We’re now looking to find out just what was so special about the Preseli Hills 5,000 years ago, and whether there were any important stone circles here, built before the bluestones were moved to Stonehenge.”
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