In the middle of a wide, grassy meadow in southern England, a ring of carefully arranged stones forms one of the most famous and most studied prehistoric monuments in the world. But while scientists have long puzzled over Stonehenge and the other intricate archaeological formations nearby, a new announcement suggests that all this time, they may have completely missed the biggest stone monument of all.
Less than two miles away from Stonehenge, something much larger was hiding deep underground, archaeologists believe, and they were only able to discover it now because of remote-sensing technology — especially ground-penetrating radar — that can map structures beneath the soil without any digging into the dirt.
As researchers with the Stonehenge Hidden Landscapes Project mapped the subterranean areas all around Stonehenge, a project that's been going on for years, "we started seeing features underneath the banks,"Vincent Gaffney, an archaeologist at the University of Bradford and one of the project leads, told Tech Insider. "We realized they were stones."
These were not just a few small rocks that could be mistaken for something else, Gaffney said, but huge stones, up to 14 feet tall — dozens of them.
Stonehenge itself is about 360 feet across, but the prehistoric monument the researchers claim to have found appears to be more than four times the size. Stonehenge includes about 90 stones, while this newly discovered monument may have had up to 200, based on their calculations.
Researchers have only detected about 40 intact stones and about 30 partial stones in the "superhenge" circle, but there are many more regularly spaced "sockets" that appear to mark places additional stones once were.
Here's a visualization of what they think the site looked like thousands of years ago:
If the researchers' extrapolations are correct, that means the size of the newly discovered monument would have dwarfed Stonehenge. And the number of people needed to build it would have been "enormous."
"That doesn't mean the site is more important than Stonehenge," Gaffney explained. "Stonehenge is a unique and paramount monument. But in simple number, [this] exceeds it."
The whole complex appears to be a C-shaped formation that had been buried beneath Durrington Walls, already the site of one of the largest known henge monuments in the world. (A henge is simply a bank of earth with an interior ditch, usually in a circular formation; approximately 80 have been found throughout the United Kingdom.) Physical evidence of a village — possibly "the largest Neolithic village ever found in Britain"— was also discovered in the area in 2007.
Even with the remote-sensing technology, parts of what they believe to be this C-shaped monument are inaccessible, so researchers can't be sure of the size or shape of the entire thing. But Gaffney said he was confident extrapolating from the clear pattern they observed.
The Durrington Walls henge, first partially excavated in the late 1960s, was already considered a rather remarkable Neolithic earthwork that appeared to have some ritualistic or religious use that archaeologists could only guess at. But it was never compared directly to Stonehenge, Gaffney said, "because there were no stones."
The latest discovery suggests that the Durrington Walls henge (believed to be about 4,500 years old) may have in fact been built directly on top of this even older stone monument — after the stone monument was "deliberately buried," Gaffney said.
Potentially — if it hadn't been buried — it could have been the largest stone monument in the UK, he said. "This would have survived if the people at the time hadn't destroyed it."
The stones that archaeologists detected underground seem to have been "toppled and incorporated into the [Durrington Walls] mound, as often happens with societies when major changes occur," Gaffney told us. "We're seeing with this monument a change in belief structure," perhaps suggesting that one society was ascendant, while another was being destroyed. "This really was the equivalent of pulling down one cathedral and replacing it with another."
It's unclear why Stonehenge survived while this stone monument was toppled, but Gaffney suspects that even though the monuments appear similar to the casual observer, their different alignments may actually reflect different belief structures.
Julian Thomas, an archaeologist at the University of Manchester, called the finding "astonishing, given that this is one of the most densely studied landscapes in British prehistory." But he also said that "it's not entirely unexpected."
Thomas, collaborating with Mike Parker Pearson and others, worked on excavations at Durrington Walls several years ago and found "what appeared to be features dug to put something in that were never filled."
While that finding, using more traditional archaeological methods, may have just scratched the surface, Thomas stressed that it was impossible to actually know exactly what Gaffney's team found until there's an actual excavation.
It's also impossible to date the monument without digging it up. ("It's a World Heritage site, so you can't just dig willy-nilly," Gaffney countered.) And without knowing when the massive structure was created, it's hard to be certain exactly where it fits into the history of the UK.
Context can be crucial in making sense of all the monuments in the Stonehenge area.
"We think of Stonehenge as iconic, but it doesn't sit in isolation, and it never sat in isolation throughout its history," Thomas told us. "It keeps coming back again and again and surprising us. There's more and more going on there."
For now, the Stonehenge Hidden Landscapes Project is focusing on publishing their discovery, which still has yet to be subjected to peer review.
In the meantime, in a place so full of history, it may seem difficult to believe that a massive, potentially hugely significant monument is buried out of sight, directly beneath an area regularly swarmed by tourists — and archaeologists.
But "these stones are there, no doubt about that," Gaffney told us. "What they mean? Well, that's something different."
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