The secrets of the stones
1 Where on Earth did the stones come from?
New technology is pinpointing the sources of the huge monoliths
Stonehenge shouldn’t be there. Its great standing stones – their total weight originally equivalent to that of 13 blue whales – loom starkly from a landscape without rock outcrops. So where were they quarried?
The 12th-century historian Geoffrey of Monmouth wrote that giants had carried the megaliths from Africa to Ireland, and that Merlin then took them on to Salisbury Plain. Others such as the 16th-century lawyer John Rastell thought the stones had been moulded on the spot out of cement.
The 18th-century antiquary William Stukeley observed that not all of the stones were of the same type. He agreed with an earlier suggestion that the largest – sandstone blocks known as sarsens – hailed from near Marlborough, about 20 miles north of Stonehenge. But what of the other, smaller monoliths known as bluestones?
Africa and Ireland continued to be suggested as possible sources. One theory posited that they had arrived with ancient Greek tin traders, used as ballast in their ships. Perhaps they came from Brittany or Finland; British sources mooted included Dartmoor and Edinburgh. Then, in 1921, geologist Herbert Thomas established that Stonehenge’s bluestones had been quarried from the Preseli Hills in Pembrokeshire. But how did they get to Stonehenge? Were they transported by Neolithic people, or could they have been carried east by glaciers? Thomas had no doubt that humans were responsible, and most experts since have agreed. However, the glacier theory lingers, supported less by solid geological evidence than by disbelief that anyone would have travelled so far – 150 miles in a straight line – to source these megaliths some 5,000 years ago when they were quarried.
Over the past few years, new lab technologies have enabled geologists Richard Bevins and Rob Ixer to confirm that Pembrokeshire was indeed the
