Stonehenge, a Neolithic wonder in southern England, has vexed historians and archaeologists for generations with its many mysteries: How was it constructed? What function did it provide? Where did its towering sandstone boulders arrive from?
That previous problem may well lastly have an remedy following a analyze published Wednesday identified that most of the big stones — recognized as sarsens — seem to be to share a typical origin 25 kilometers (16 miles) away in West Woods, an place that teemed with prehistoric exercise.
The obtaining boosts the idea that the megaliths were introduced to Stonehenge about the very same time: about 2,500 BCE, the monument’s 2nd phase of development, which in convert could be a sign its builders had been from a remarkably structured modern society.
It also contradicts a prior suggestion that one particular substantial sarsen, the Heel Stone, came from the speedy vicinity of the site and was erected before the many others.
The new paper appeared in the journal Science Improvements.
Guide writer David Nash, a professor of bodily geography at the College of Brighton, explained to AFP he and his team had to devise a novel system to evaluate the sarsens, that stand up to nine meters tall (30 feet) and weigh as a great deal as 30 metric tons.
They first utilized portable x-rays to assess the chemical composition of the rocks, which are 99 p.c silica but have traces of a number of other factors.
“That confirmed us that most of the stones have a popular chemistry, which led us to establish that we’re wanting for just one main supply in this article,” mentioned Nash.
Subsequent, they examined two main samples from a person of the stones that ended up acquired all through restoration operate in 1958 but which then went missing until eventually resurfacing in 2018 and 2019, respectively.
They carried out a extra innovative assessment on these samples employing a mass spectrometry machine, which detects a more substantial array of elements at a better precision.
The resulting signature was then compared to 20 probable supply sites for these sedimentary rocks, with West Woods, Wiltshire uncovered to be the closest match.
Only the 17th century English natural thinker John Aubrey had earlier postulated a hyperlink between “Overton Wood,” likely a former title for West Woods, and Stonehenge.
Past work has located that Stonehenge’s scaled-down “bluestones” came from Wales, about 200 kilometers (160 miles) to the west, and the new review says that they and the sarsens had been put at the similar time.
“So it ought to have been an monumental endeavor likely on at that time,” claimed Nash. “Stonehenge is like a convergence of resources remaining brought in from different areas.”
Just how the early Britons had been able to transportation the boulders weighing up to 30 tons a distance of 25 kilometers remains unidentified — nevertheless the prevailing strategy is they ended up dragged together sleds. The site’s significance also remains mysterious.
“I imagine you are looking at a really arranged society there,” additional Nash.
As for why they picked West Woods, he explained, it could have been a situation of pragmatism as it was one particular of the closest web pages.
But the location was also a hive of Early Neolithic action.
It is house to a large ancient burial internet site known as a barrow, a big circular earthwork, prehistoric cultivated fields that are now woodland, and a polissoir — a rock applied to sharpen historical stone axes.
Nash reported that the procedure the analysis workforce experienced devised could aid answer even further archaeological thoughts, these kinds of as the route utilised to transportation the boulders — which can be inferred if sarsen chippings are uncovered at waypoints.
He and his team also hope to use the methods on other ancient sarsen sites scattered all over Britain.