After spending four years scanning the ground surrounding the world’s most famous prehistoric monument, University of Birmingham archeologists have produced a map of unprecedented detail of the earth beneath Stonehenge. The findings have yielded many unexpected surprises that are transforming our understanding of this ancient landscape, including details of a nearby 1.5 kilometer-round “super henge” and a plethora of previously unknown monuments.

For the survey, named the “Stonehenge Hidden Landscape Project,” researchers ditched their digging tools and turned to magnetometers and ground penetrating radars that they dragged around with quad bikes. These techniques, combined with aerial photography and airborne laser scanning, produced high-resolution 3D maps of the iconic landscape and the hidden secrets below.

Stonehenge Hidden Landscapes Project/University of Birmingham/ Ludwig Boltzmann Institute

The survey revealed hundreds of new features around the megalithic monument which lies on Salisbury Plain, Wiltshire. Among the findings were 17 previously undiscovered ritual monuments that suggest Stonehenge did not stand alone, and also dozens of burial mounds, some of which were older than the 4,400-year-old monument. A huge 6,000-year-old timber building beneath one of the earthy mounds was also revealed which they believe was probably used for bizarre burial rituals that involved removing the flesh from the dead.

Geert Verhoeven/University of Birmingham

They also identified novel features of a 3-kilometer-long, 100-meter-wide ditch nearby called the Cursus that was thought to serve as a barrier for Stonehenge. They found several gaps in the ditch and also giant prehistoric pits which appear to form astronomic alignments. On midsummer’s day, the eastern pit’s alignment with dawn and the western pit’s alignment with dusk meet at the point where Stonehenge was built almost 500 years later.

The new map also yielded exciting information about the less well-known Durrington Walls, or “super henge.” Located only a small distance from Stonehenge, this gargantuan monument is probably the largest of its kind with a circumference of more than 1.5 kilometers (0.93 miles). The images hinted that at one stage, as many as 60 giant stones may have bordered the monument, some of which were 3 meters high. The holes left by the stones seem to indicate that they were pushed over which would make sense given that several lines of evidence suggest ancient cultures often altered or dismantled their monuments. The researchers also believe that some of these stones may still lay buried, but unfortunately the technology used to scan the ground could only penetrate a depth of 3 meters.

“This radically changes our view of Stonehenge,” said Vince Gaffney, head of the project at Birmingham University. “In the past we had this idea that Stonehenge was standing in splendid isolation, but it wasn’t… it’s absolutely huge.”

The team’s findings will feature in a major new BBC series entitled “Operation Stonehenge: What Lies Beneath.”

[Via University of Birmingham, Guardian, BBC News and Nature]

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