More than 4,500 years ago, at least 90 huge stone monoliths lined an impressive “arena” that may have been used for religious rites or solstice rituals.
Now lying on their sides covered by more than a metre of earth, they remained undiscovered until archaeologists equipped with ground-penetrating radar probed the area around the famous stone circle on Salisbury Plain.
They are the most important find to emerge so far from the Hidden Landscapes project which is using state-of-the-art technology to map “invisible” archaeological features embedded in the Wiltshire countryside.
The stones, some measuring nearly 4.5m, were placed along the south-eastern edge of what later became the Durrington Walls “superhenge”, a circular enclosure ringed by a ditch and bank that at over 1.5km across is the largest earthwork of its kind in the UK.
@khrizmo another fantastic discovery, & yet another layer to the mysteries of Salisbury Plain & it's far distant past.— Joanna M Shaw 💙 (@joannamshaw1970) September 7, 2015
Experts believe the stones, which may have been imbued with magical properties, were not originally part of the henge but were deliberately toppled before being incorporated into it.
Professor Vince Gaffney, from the University of Bradford, one of the archaeologists leading the project, said: “We’re looking at one of the largest stone monuments in Europe and it has been under our noses for something like 4,000 years.
“It’s truly remarkable. We don’t think there’s anything quite like this anywhere else in the world.
“This is completely new and the scale is extraordinary.
“We presume it to be a ritual arena of some sort.
“These things are theatrical. They’re designed to impress and impose; to give the idea of authority to the living and the dead. It really does create a massive impression, and was clearly important enough to have been drawn into the developing landscape.”
Ninety stones have been discovered so far, and there may be more.
What kind of material they are made of is unknown, but they could be similar to the giant sandstone “sarsens” of Stonehenge.
Gaffney says the stones may have been planted by the same people who built Stonehenge, but is sceptical about a direct link between the two monuments.
Precisely why the stones were put there remains a mystery but part of Durrington Walls is aligned with the rising sun on the winter solstice, the year’s shortest day, which may be significant.
The archaeologists believe that at some stage the stones were pushed over and incorporated into the emerging henge. It was not an act of vandalism but a deliberate attempt to preserve whatever it was about the stones that seemed so important.
“There was a transformation in the landscape that we do not understand,” said Gaffney.
“The stones had significance. These are special places. Societies are mobilised, as with the great cathedrals, to create these things.”
The discovery at Durrington Walls was unveiled at the British Science Festival, taking place this week at the University of Bradford.
At the same event last year, the international team revealed a host of previously unknown archaeological features that had been hidden around Stonehenge.
They included a 108ft long burial mound containing a massive wooden building whose timber foundations lay under the soil.
The ongoing survey is using a suite of technologies to peer below the ground, including penetrating radar, electromagnetic induction, magnetometry, electrical resistance mapping, and lasers.