Mystery concrete circle identified as base of WWIII warning system

A Cold War mystery at what was one of Britain’s most secret and sensitive sites has been solved after volunteer researchers finally identified the real purpose of a 50-metre concrete ring that has baffled experts for years. The structure, at Orford Ness National Nature Reserve, a formerly top-secret military testing ground now left to nature on the Suffolk coast, has puzzled visitors and staff since the National Trust took over the 2,000-acre site in 1993.

Now thanks to the dedication of a band of researchers, and a transatlantic adventure for two friends – Steve Clifton and Olaf Kirchner – the concrete ring has been identified as part of an innovative over-the-horizon radar known as the ‘R-System’. It was designed and built by the US Air Force in the 1960s to detect ballistic missile launches and nuclear explosions during the Cold War. The concrete ring that survives supported a steerable helical transmitter and featured double rows of receivers – some 150metres from end to end that could detect activity thousands of miles away.

By the end of the 1960s, the technology had been replaced with satellites. Only eight structures of this design are believed to have been constructed anywhere in the world – including at Roswell in New Mexico and Muirkirk in Maryland. Olaf and Steve first visited Orford Ness in 2018 as part of a guided tour and were captivated by its otherworldly landscape and mysterious military buildings.

They later joined the volunteer-led research group, International Research Group Orford Ness (IRGON) to help research the site and the top-secret military experiments that took place there between 1915 and 1972 – including the First, Second and Cold Wars. In 2020, using technical drawings, aerial photographs and declassified files, another National Trust volunteer and researcher, David Warren, formed a working theory about the purpose of the concrete ring. The question was, what else was known about the global network of R-System radars, and what part did Orford Ness play? I

n October last year, Steve and Olaf travelled to Muirkirk in Maryland, where they photographed a similar concrete ring and met with 94-year-old Edwin Lyon, chief designer of the R-System. He confirmed its existence and provided a rare snapshot into Cold War history, and shared valuable photographic and video evidence from 60 years earlier.

Olaf said: “It turned out that Ed himself had no idea that this radar system had been set up in England. He’d had to get security clearance to talk to us about it and we listened in awe for over two hours, getting first-hand accounts of Cold War intelligence gathering systems. It was a researcher’s dream.”

After interviewing Ed, the two friends travelled to Roswell, New Mexico, where they located a second ring and confirmed that the precise location and orientation of the extensive system of aerials were similar to those on Orford Ness. Olaf said: “Due to the extreme secrecy under which they worked, people on Orford Ness never spoke of their projects and often took their details to their grave. While the reports covering their work are now mostly declassified, finding them is often difficult.

“Even large, obvious remnants on the shingle of Orford Ness, just like the concrete ring, still await explanations, which is why we’re working in partnership with the National Trust to tell the stories of the place and its people and ensure their achievements are never forgotten.”

Angus Wainwright, Regional Archaeologist for the National Trust’s East of England region, says: “This structure has always intrigued me, it’s one of Orford Ness’s many mysteries. Like all the places we care for, our understanding of what happened on Orford Ness is constantly evolving. Research is important to us, and we are always trying to further our understanding.

“It’s only through the tenacity of these researchers that its secret function has now been revealed.”

Orford Ness is open to visitors on Thursdays and Saturdays until the end of September and can only be accessed by the National Trust ferry, Octavia. For more information, visit nationaltrust.org.uk/orfordness