THE people who built Stonehenge are renowned for hauling the megalithic bluestones over 220km from the Preseli Mountains in Wales to their final home on Salisbury Plain.
But perhaps that mammoth journey proved too much for them because when it came to sourcing the larger sarsen stones later on, they looked far closer to home. Archaeologists from English Heritage and the University of Sheffield have finally solved a centuries-old mystery and concluded that the sarsens originated in the West Woods of the Marlborough Downs, just 24km north of Stonehenge and not far from the Neolithic monument site at Avebury.
The breakthrough came when a core - drilled from 'Stone 58' during repairs in the 1950s - was returned to English Heritage from the US last year and finally gave archaeologists the chance to analyse the chemical make-up without damaging the stone.
Historian Susan Greaney said: "The bluestones, we've known, come from mid-west Wales and they were easy to source. The large stones are pretty uniform and just look like a big block, so it's difficult to interrogate them and find where they are from."
Researchers used X-ray spectrometry to look at the very small trace elements and it was found the Stonehenge sarsens matched those in the Marlborough Downs. They weigh about 20 tonnes but some are as heavy as 30 tonnes and the largest is 30ft long.
"There are no sarsens of this size left in the Downs, that's why it's been such a mystery and some people have suggested they come from elsewhere as you get outcrops in other places," Ms Greaney added. "To be able to pinpoint the area that Stonehenge's builders used to source their materials around 2,500BC is a real thrill."
The west wood was overlooked because it's under ancient woodland but there are still sarsens buried among the trees. (© Daily Telegraph, London)