Scotland Surprise: Stonehenge’s Altar Stone Traced 500 Miles North in Stunning Discovery

A new study details the "shocking" discovery that the six-ton "altar stone" at Stonehenge originated in Scotland, nearly 500 miles away, though most of the monument's other stones originated in England and Wales.

The ancient monument in Wiltshire in southern England was erected nearly 5,000 years ago, and features a large outer circle of stone tablets called "sarsens," which support horizontal rocks called lintels, and an inner circle of "bluestones." The altar stone sits at the center, measuring about 16 feet long and weighing more than six tons.

Researchers at Curtin University in Australia led the study, published in the journal Nature, in collaboration with Aberystwyth University, The University of Adelaide and University College London.

Researchers analyzed the age and chemical composition of mineral grains within the altar stone, which is sandstone, and found it matched rocks from the Orcadian Basin in northeast Scotland. The slab was long believed to have originated in Wales, like many of the other stones.

“Our analysis found specific mineral grains in the Altar Stone are mostly between 1000 to 2000 million years old, while other minerals are around 450 million years old,” said lead author Anthony Clarke, a PhD student at the Timescales of Mineral Systems Group in Curtin’s School of Earth and Planetary Sciences.

“This provides a distinct chemical fingerprint suggesting the stone came from rocks in the Orcadian Basin, Scotland, at least 750 kilometers away from Stonehenge," Clarke said.

“Given its Scottish origins, the findings raise fascinating questions, considering the technological constraints of the Neolithic era, as to how such a massive stone was transported over vast distances around 2600 B.C.," he said.

Moving the stone was not just a matter of technological know-how, but also of widespread "societal organization," according to co-author Professor Chris Kirkland, also from the Timescales of Mineral Systems Group.

“Our discovery of the Altar Stone’s origins highlights a significant level of societal coordination during the Neolithic period and helps paint a fascinating picture of prehistoric Britain,” Kirkland said.

“Transporting such massive cargo overland from Scotland to southern England would have been extremely challenging, indicating a likely marine shipping route along the coast of Britain. This implies long-distance trade networks and a higher level of societal organization than is widely understood to have existed during the Neolithic period in Britain," Kirkland said.

Co-author Robert Ixer of the UCL Institute of Archaeology described the finding that the stone is Scottish and not Welsh as "shocking."

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“The work prompts two important questions: why and exactly how was the Altar Stone transported from the very north of Scotland, a distance of more than 700 kilometers, to Stonehenge?” Ixer said.

Co-author Professor Richard Bevins from Aberystwyth University said additional research will be needed to determine the exact location of the altar stone's origin.

“While we can now say that this iconic rock is Scottish and not Welsh, the hunt will still very much be on to pin down where exactly in the north-east of Scotland the Altar Stone came from," Bevins said.

TMX contributed to this report.