Stonehenge is so much more than just a monumental feat of ancient engineering—it’s also a logistical marvel. Multiple generations of Neolithic designers relied on communal teamwork and clever construction techniques to precisely place each of the site’s gigantic megaliths about 5,000 years ago. Two primary types of stone known as sarcens and bluestones make up the formation. Paleoarchaeologists previously traced most of the sarcens to about 15 miles away to present-day Marlborough, England, while many of the bluestones originated in Wales.
The famed Altar Stone is far more perplexing, however. The central, six-ton sandstone megalith likely came from a region in Scotland about 400 miles away. How a prehistoric society managed to scoot the boulder so far without complex tools or transportation methods has perplexed researchers for years.
Many researchers have theorized that melting Ice Age glaciers likely helped passively shift the Altar Stone closer to southern England’s Salisbury Plain around 2500 BCE, shortening the transport distance for Stonehenge’s creators. But in 2024, a team at Curtin University used chemical analysis to determine that glaciers simply weren’t the only factor behind the megalith’s move. Now, that same team has combined ice-sheet modeling and mineral grain dating to more precisely locate the Altar Stone’s original home. Their findings, published today in the Journal of Quaternary Science, further underscore how humans played a huge part in getting their centerpiece to Stonehenge.
“Rather than being carried naturally by ice, the evidence points to a deliberate, carefully planned movement across a challenging and varied landscape,” Anthony Clarke, a geochemist and study co-author, said in a statement.
Although glaciers possibly transported many large rocks as far south as Dogger Bank in the North Sea, Clarke explained that geological modeling showed that “no viable glacial pathways” ever linked the Altar Stone’s source region to Stonehenge. This further underscores how Neolithic communities were necessary to move it to its final spot.
“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,” he added.
While the exact methods remain a mystery, Clarke and colleagues believe the Altar Stone was almost certainly moved in stages, possibly through a combination of overland and river travel routes.
“The stone would still have needed to be moved hundreds of kilometers by people,” Clarke concluded.