Stonehenge's six-tonne Altar Stone was carried over 430 miles from northeast Scotland to its final resting place in Wiltshire, according to a new study in the Journal of Quaternary Science. The research combines mineral grain analysis with ice sheet modelling to trace the stone's origins, ruling out glacial transport for the entire journey and pointing to a complex, multi-stage human effort.

From Caithness to Wiltshire: The 430-Mile Trail

The study,led by researchers who analysed mineral grains from the Altar Stone, pinpoints its source to the Caithness region of northeast Scotland. By modelling ancient ice sheets, the team proposes that the stone first moved via glacier across what is now the North Sea to the Dogger Bank area — a land bridge that flooded around 7,000 years ago. According to the study, humans then took over, hauling the stone at least 250 miles overland and by boat to reach Stonehenge on Salisbury Plain.

Glaciers Did the First Leg – Humans Finished the 250-Mile Haul

The research highlights that while glaciers could have moved the stone out of Scotland, human agency was critical for the southern half of the journey. "Even if the stone was transported from Dogger Bank, it would still have required movement over some 400km [250 miles], implying considerable Late Neolithic capacity for organisation, labour mobilisation and overland and marine transport," the study authors wrote. This challenges previous assumptions that the Altar Stone came from Wales, as the other bluestones did.

The Dogger Bank Link: A Flooded Stepping Stone

A key part of the proposed route is Dogger Bank, a now-submerged plain that once connected Britain to continental Europe. The study suggests Mesolithic poeple recovered the stone from this area before it was inundated by rising seas.. From there, the stone could have been transported by boat through sheltered waterways, up the Thames river system, and then overland along the Berkshire Ridgeway — a prehistoric high-ground route.. The timing would have required the stone to be moved well before the Neolithic period, implying a previously unknown layer of cultural significance.

Why the Single-Trip Theory Collapses

The study argues that the Altar Stone's journey was not a single, direct episode but a multi-phase process spanning a large temporal gap. "The study highlights the need for human agency in the transportation of the Altar Stone, which challenges the plausibility of a single episode of transport," the authors note. Instead, the stone may have held prolonged cultural significance, with different groups moving it over hundreds or thousands of years. This reframes Stonehenge not as a static monument but as a site with deep roots in prehistoric mobility.

The Unanswered Question: Who Carried It and Why?

Despite the new geological evidence, the study leaves open key questions. The exact human route remains speculative — no archaeological evidence of intermediate handling sites has been found. Moreover, the cultural motivation for moving such a heavy stone over such a distance is unknown. The report does not identify which specific group or groups were responsible, nor does it explain why the Altar Stone — unlike other Stonehenge stones — was brought from so far away. Future research will need to look for artefacts along the proposed route and examine whether similar stones from the same Scottish source appear elsewhere in Britain.