On a misty moor in Cornwall, a monument long thought to date to the medieval period has turned out to be more than meets the eye. King Arthur’s Hall, a mysterious stone and turf structure on Bodmin Moor, is far older than anyone could have imagined — around 4,000 years older, in fact.

A recent survey, led by researchers from the University of St Andrews, Reading, and Newcastle, has dated the origins of the structure to the middle of the Neolithic period. The discovery reframes our understanding of this enigmatic site. It is a relic from a distant past predating even the stone circles of the Bronze Age.

A Monument Unlike Any Other

Dr. Tim Kinnaird, from the School of Earth and Environmental Sciences at St Andrews, spearheaded the investigation using optically stimulated luminescence (OSL). OSL dates sediment by measuring when it was last exposed to sunlight. The results show that rather than being constructed around 1000 CE as previously thought, King Arthur’s Hall dates back to about 3000 BCE.

“It’s extremely exciting that we’ve finally been able to date construction of this enigmatic monument, previously grounded in myths and legends,” said Dr. Kinnaird. The new findings push the timeline back by millennia, suggesting that the structure was built by early farming communities who were beginning to settle the rugged landscapes of southwest England.

The structure measures 49 by 21 meters and is lined with 56 standing stones. The initial belief was that this rectangular earthwork served as a medieval livestock pen. But the soil samples tell a very different story and researchers now have to consider the monument’s place in the context of a prehistoric landscape.

James Gossip, an archaeologist with the Cornwall Archaeological Unit, emphasized the site’s uniqueness. “There isn’t another one of these anywhere. There is nothing built at that time or subsequently in prehistory that is a rectangular earth and stone bank with a setting of stone orthostats around the interior.” The site’s design is distinct in European archaeology, and its original purpose remains a subject of debate.

So why build a massive stone enclosure on a desolate moor? The researchers suggest that King Arthur’s Hall may have served as a gathering place for early communities, potentially for rituals or seasonal celebrations. “The thinking is that these are meeting points for communities, perhaps to mark special occasions or to carry out ceremonies,” Gossip explained.

An Old Mystery

The discovery was part of a larger project commissioned by Cornwall National Landscape to explore and preserve historic sites in the region. Initial excavations, sparked by local enthusiasts, led to questions about the site’s true age and purpose. Further investigations revealed that the ancient builders had dug through the earth of Bodmin Moor to reach the granite beneath, piling it up into ramparts and encasing the structure with standing stones.

The site’s name “King Arthur’s Hall” conjures images of knights and medieval legends. But any connection to the fabled king is purely symbolic. This connection with the legend of Arthur is a much later development, likely originating in the Middle Ages when myths were often used to explain mysterious ancient structures.

“The Middle Ages was a period when the Arthur name starts being attributed to all sorts of unusual sites that the local population at the time probably didn’t understand,” Gossip noted.

Pete Herring, president of the Cornwall Archaeological Society, added, “The romantic-sounding 16th-century name King Arthur’s Hall tells us that here is a place regarded by the moorland community as something ancient and unfathomable, like other sites attributed to Arthur. Science has responded to that name’s challenge, providing a very early date of origin, and two other dates, later prehistoric and medieval, when there was activity at the enclosure.

As researchers continue to explore the site, they hope to uncover more clues about the people who constructed it and their reasons for building such a unique and enduring monument.