Researchers, from Sheffield Hallam University and Curtin University, Australia, have found that it is possible that the Altar Stone travelled from the Orcadian Basin in Scotland and was deposited at Dogger bank via glacial transport during Britain’s last ice age by studying ice flows.
Stonehenge’s central Altar Stone is a six-tonne sandstone megalith now believed to have originated in northeast Scotland, around 700km from Salisbury Plain, underscoring the extraordinary scale of its journey.
Researchers have now focused on what that journey may have looked like, combining mineral grain dating with ice-sheet modelling to pinpoint the stone’s origin and test whether glaciers could have carried it south.
Dr Remy Veness, co-lead author of the paper from Sheffield Hallam University, said: “We recently discovered that the origin of the Altar Stone is northeast Scotland, but how it travelled 700km to Salisbury Plain is widely debated.
“Our research gives a new plausible explanation for part of the journey to Salisbury Plain.
“What is exciting about these findings is that they could imply that the people of Doggerland attached cultural significance to the Altar Stone long before it was incorporated into Stonehenge. Hypothetically, the Altar Stone could have been significant enough to be willing to move the stone at least twice; First to potentially save it from being submerged by rising sea levels at the end of the last ice age and then again to its final resting place on Salisbury Plains.”
Dogger Land was a neolithic site off the east coast of England and is now submerged under the North Sea. There is no natural outcropping of rock on Dogger Land, any large rocks would have only been available there via glacial transport.
The paper suggests that from Dogger Land, the Altar Stone could have been moved close to the Berkshire Ridgeway, the oldest road in Europe, which was active at the time of Stone Henge and could have eased or encouraged travel to Salisbury Plain.
Co-lead author Dr Anthony Clarke, from the Timescales of Minerals Systems Group within Curtin’s School of Earth and Planetary Sciences, said the findings suggest the journey was far from simple and likely required careful planning across multiple stages.
“Rather than being carried naturally by ice, the evidence points to a deliberate, carefully planned movement across a challenging and varied landscape,” Dr Clarke said.
“Our modelling shows glaciers may have transported rocks part of the way during the last Ice Age — potentially as far as Dogger Bank in the North Sea — but not into southern England, meaning the stone would still have needed to be moved hundreds of kilometres by people.
“The research indicates there were no viable glacial pathways linking the source region directly to Stonehenge, reinforcing the conclusion that human transport was required.
“Instead, this suggests the stone was likely moved in stages, potentially combining overland hauling with river or coastal transport where possible.”
Dr Clarke said the findings reveal a level of organisation and cooperation among Neolithic communities not previously fully appreciated.
“Transporting a stone of this size over such a long distance would have required planning, coordination and a deep understanding of the landscape – not to mention tremendous determination,” Dr Clarke said.
“The study demonstrates how combining geological analysis with computer modelling can help resolve long-standing questions about how Stonehenge was built.”
Future research will aim to pinpoint the Altar Stone’s exact source in northeast Scotland and further investigate possible transport routes used by prehistoric communities.
The study, ‘From Highlands to henge: Refining the provenance and transport pathways of Stonehenge’s Altar Stone’ (DOI:10.1002/jqs.70080), was published in the Journal of Quaternary Science.
