What Lies Beneath Stonehenge: Unearthing Major Secrets

Stonehenge will never be the same again...

That's what experts with the Stonehenge Hidden Landscapes Project are saying after discovering 17 previously unknown ritual monuments dating to the period when Stonehenge achieved its iconic shape.

The result of this project is a huge digital map of the monuments and evidence of landmarks hidden beneath the grounds surrounding Stonehenge - including details on the massive Durrington Walls, the world's largest "super henge."

Vincent Gaffney, the project leader and Chair in Landscape Archaeology and Geomatics at the University of Birmingham, liked to refer to the ground around Stonehenge as "terra incognita."

"There was sort of this idea that Stonehenge sat in the middle and around it was effectively an area where people were probably excluded," he told Smithsonian Magazine. "Of course that sort of analysis depends on not knowing what's actually in the area around Stonehenge itself."

And now, thanks to remote sensing techniques and extensive geophysical survey of the surrounding landscape, Gaffney knows far too much about Stonehenge to leave things to such guesswork.

"This project has revealed that the area around Stonehenge is teeming with previously unseen archaeology," he excitedly announced in a recent release. "New monuments have been revealed, as well as new types of monument that have previously never been seen by archaeologists."

According to the project results, the ground around Stonehenge is packed with burial mounds, including a large and long barrow that dates back even before Stonehenge was made. (Scroll to read on...)

Inside this barrow, they found evidence of a timber building over 100 feet long that was likely used for ritual dehumanization - in which priests would strip a body of its flesh in a process called excarnation - prior to burial.

New details the Durrington Walls, a massive, mile-long ritual monument located not far from Stonehenge, were also revealed, with cutting-edge mapping technologies showing new dimensions to the now mostly-gone structure.

Past analysis of Stonehenge has led some to believe that the structure has to do with a passing of the seasons. Thanks to this four-year survey, more evidence backs that theory.

Two pits along the Cursus - a circular trench that early archaeologists thought resembled a Roman horse racing course  - are precisely aligned to mark the sunrise and sunset on Midsummer's Day as seen from the heel stone of Stonehenge.

Strangely, these pits, which must have taken a significant amount of manpower and time to make, were not built within the same time-frame as Stonehenge.

"The structures guide the builders. Once you have some things in place, other things happen because those already exist," Gaffney explained to BBC. "Once you have some things in place, other things happen because those already exist."

Amazingly, the same technologies used to make these findings also revealed hundreds of burial mounds, Bronze Age, Iron Age and Roman settlements, and ancient agricultural fields at a level of detail never previously seen. (Scroll to read on...)

"Developing non-invasive methods to document our cultural heritage is one of the greatest challenges of our time and can only be accomplished by adapting the latest technology such as ground-penetrating radar arrays and high-resolution magnetometers," added Wolfgang Neubauer, the Director of the Ludwig Boltzmann Institute. "No landscape deserves to benefit from a study at this level of detail more than Stonehenge."

As of yet, no one has started actually shoveling to verify these findings, but Gaffney certainly doesn't doubt his team's work.

"This is among the most important landscapes, and probably the most studied landscape, in the world," he told the Smithsonian. "And the area has been absolutely transformed by this survey. Won't be the same again."

A study detailing initial findings and imaging technologies used to survey the grounds was published in the journal Archeological Prospection back in 2012.

The full results will also be detailed in a documentary entitled "Operation Stonehenge: What Lies Beneath," which will air on BBC Two at 8pm (BST) on Thursday, Sept. 11.