Calanais standing stones at sunset with purple sky

Ancient secret of stone circles revealed at Calanais

Published: 23/12/2019

New evidence of a massive lightning strike at the centre of a hidden stone circle in the Outer Hebrides may help shed light on why these monuments were created thousands of years ago.

Calanais Stones at daybreak
Tursachan Chalanais/Calanais Stones

The Calanais Virtual Reconstruction Project is a joint venture led by the University of St Andrews and supported by Highlands and Islands Enterprise (HIE) and has uncovered a potential link between ancient stone circles and the forces of nature.

While studying the prehistoric Tursachan, the main stone circle at Calanais on the Isle of Lewis, the project team surveyed nearby satellite sites to reveal evidence for lost circles buried beneath the peat.

One rarely-visited site surveyed, known as Site XI or Airigh na Beinne Bige, now consists of a single standing stone on an exposed hillside overlooking the great circle. 

Geophysics revealed that not only was the stone originally part of a circle of standing stones, but also that there was a large, star-shaped magnetic anomaly in the centre - either the result of a single, large lighting strike or many smaller strikes on the same spot.

Project leader Dr Richard Bates, of the School of Earth and Environmental Sciences at the University of St Andrews, said:

“Such clear evidence for lightning strikes is extremely rare in the UK and the association with this stone circle is unlikely to be coincidental.

“Whether the lightning at Site XI focused on a tree or rock which is no longer there, or the monument itself attracted strikes, is uncertain.

“However, this remarkable evidence suggests that the forces of nature could have been intimately linked with everyday life and beliefs of the early farming communities on the island.”

The researchers were also able to virtually recreate another nearby circle, with the help of the Smart History team based in the University of St Andrews School of Computer Science, which had been lost with its stones either buried or lying flat.

Known as Na Dromannan, careful scanning of the stones allowed a full 3D model to be built allowing the passage of the sun and moon around this circle to be tracked for the first time in four millennia.

Dr Bates added: “For the first time in over 4000 years the stones can now be seen and ‘virtually’ walked around. 

“Everyone will be able to visit this remote site and get a real sense of what it was like just after it had been constructed.  We have only just scratched the surface of this landscape and already we can get a feel for what might be buried out there waiting for discovery.” 

The team hopes to return to Lewis next year to undertake further surveys both on land, and in the waters, around the Tursachan at Calanais, where the old landscape has been flooded by rising sea levels. 

Ann Marie Reid, senior project manager at HIE, said:

“We’re delighted the Calanais virtual reconstruction project, funded through HIE’s 2017 YHHA digital adoption scheme, has led to these new fascinating archaeological discoveries and there is the possibility of further academic research relating to the Calanais site. It’s fantastic to hear the research findings will be available to see at the Calanias Visitor Centre further adding to Calanias’ impressive cultural offering.  

Dr Alison Sheridan, Director of Urras nan Tursachan, the Calanais based charitable trust that partnered this research, said: “This is a thrilling discovery that helps us get inside the minds of the people who built the stone circles at and around Calanais. There is much still to find out about the so-called ‘satellite’ circles of Neolithic Calanais and this provides an important first step. The modelling of Na Dromannan also helps us investigate whether this circle was astronomically aligned.”

Some of the research findings will be available to see at the Calanais Visitor Centre, on the Isle of Lewis in 2020.

The venture is also supported by the University of Bradford.