New research indicates that humans, rather than a glacier, probably transported the altar stone to Stonehenge from north-east Scotland. The 6-tonne sandstone monolith traveled about 750 kilometres to its current position at the monument's centre.
A study published in the Journal of Quaternary Science examined ice flow patterns during the last glacial period. Researchers led by Anthony Clarke of Curtin University found that ice from north-east Scotland mostly moved northward, with limited southward flows depositing material at Dogger Bank under the North Sea. The altar stone has been at Stonehenge for around 4500 years. Its chemical composition matches rocks from the Orcadian Basin, confirming the distant origin first identified in 2024. Clarke noted that other large stones at the site were moved by people over shorter distances. He said the builders had the capability for longer transport, adding that the project was a multi-year effort similar to the pyramids. The findings make human transport the more plausible explanation, though the exact quarry source remains unknown.