Stonehenge is one of the most iconic archaeological sites in the world, but despite its celebrity status, we still don’t know exactly who built the stone monument, what it was for, and how exactly all of its stones reached southern England’s Salisbury Plain.
New research addresses the last of these mysteries. According to a study published yesterday in Communications Earth & Environment, it probably wasn’t glaciers.
“Ice almost certainly didn’t move the stones,” Anthony Clarke, lead author of the study and a geologist at Curtin University’s Timescales of Minerals Systems Group, said in a university statement.
Human labor
If that sounds like an unusual answer, here’s the story: Researchers still debate whether Stonehenge’s bluestones—the smaller (but still massive) two- to five-ton rocks—were transported from Wales by humans or carried by glaciers. The new study shows there were no glaciers at Salisbury Plain during the Pleistocene Epoch (2.5 million to 11,700 years ago), strengthening the theory that humans did the heavy lifting. And if glaciers couldn’t have carried the bluestones because they weren’t there, it seems obvious that they couldn’t have carried any of the other stones, either.
“How Stonehenge’s building blocks arrived on Salisbury Plain remains debated, with glacial and human transport mechanisms proposed,” the researchers wrote in the paper. “Collectively, our data show Salisbury Plain remained unglaciated during the Pleistocene, making direct glacial transport of Stonehenge’s megaliths unlikely.”
The researchers reached this conclusion after searching for the traces of potential ancient glaciers in rivers near Stonehenge. They analyzed tiny grains, including hundreds of zircon crystals, and, simply put, didn’t find evidence of glaciers at the site, according to Clarke.
Searching through river sands
“If glaciers had carried rocks all the way from Scotland or Wales to Stonehenge, they would have left a clear mineral signature on the Salisbury Plain,” he explained in the statement. “Those rocks would have eroded over time, releasing tiny grains that we could date to understand their ages and where they came from. We looked at the river sands near Stonehenge for some of those grains the glaciers might have carried and we did not find any.”
As for the question of how humans moved the stones, we still don’t know. Sailboats and logs rolled over land are two possibilities, though Clarke admitted that the truth might never come to light.
I, however, still have faith in advancing technology as a means to solve this mystery. Just look at how AI is unveiling texts from ancient, Vesuvius-burnt scrolls—still wrapped.
