Each year Stonehenge draws more than a million visitors to a spot in southern England about 90 miles from London and 35 miles from Bath. Many of these visitors flock to the site on solstices and equinoxes: On those four dates each year, the barrier surrounding the megalith is lowered and visitors can move freely among the stones. Last year, it even became the site of a major climate change protest.
Despite being a magnet for visitors, there’s still much we don’t know about this prehistoric monument, including two important details: why it was built, and what it was used for. In fact, what we don’t know about Stonehenge far outpaces what we know about it. Here are some questions we have answered, as supported by decades of archaeological and historical research.
How long did it take to build?
It was built gradually—very gradually. Historians now estimate the original monument was enlarged over the course of more than 1,000 years. Ground first broke on the site some 5,000 years ago, when Neolithic Britons dug out a circular bank and ditch (or “henge”). Wooden posts were erected on the site at some point, but the stone monument that remains today was begun around 2500 B.C.E. Adjustments were made to the positions of the smaller, inner bluestones 200 to 300 years later. Etchings dating to the Bronze Age were later carved into the rocks, the first of such graffiti to adorn Stonehenge in the millennia to come.
Where did the rocks come from?
Huge boulders aren’t exactly in high supply in the grassy plains on which Stonehenge was built. Therefore, the ancient peoples who erected it likely looked elsewhere for materials. Geological evidence supports the idea that the sarsen (sandstone) that makes up Stonehenge’s towering blocks came from Marlborough Downs, 20 miles away. The smaller dolerite bluestones came from even farther away: the Preseli Hills in southwest Wales, 180 miles to the northwest.
It is still unclear how Stonehenge’s builders transported such heavy boulders such a long distance. The average sarsen at Stonehenge weighs 25 tons; the average bluestone ranges from 2 to 5 tons, and the largest weighs a whopping 40 tons. Some theories posit that they were floated to the site by river and sea vessels.
What is special about the layout of the stones?
A processional avenue connecting Stonehenge and the River Avon aligns with the summer solstice sunrise and winter solstice sunset. During the summer solstice, the sun rises above the Heel Stone, a large, unworked sarsen standing about 250 feet from the center of the monument’s stone circle.
A general aerial view of a frost covering Stonehenge on January 3,2025 in Wiltshire, England.
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Is it a burial site?
Yes—in fact, some historians believe Stonehenge is foremost a burial site. Many human remains have been found at and around Stonehenge, most of them cremated and dating to the Neolithic era. Also resting there: one unlucky decapitated man, killed—possibly executed—during the Saxon era.
Were there visitors to the site before modern-day tourists?
Yes. Stonehenge has drawn visitors for much of its history. For instance, archaeological digs have turned up Roman artifacts like coins, jewelry, and pottery fragments. It’s possible that, like modern-day visitors to the site, those Romans were just sightseeing. Others surmise that it may have become a holy site of sorts in Roman-occupied Britain.
Was Stonehenge built by the Druids?
Probably not. We don’t know anything about the culture that built Stonehenge—there are no written records for us to study. Even so, it’s highly unlikely that the Celtic high priests known as the Druids had anything to do with it. Stonehenge predates the first written mention of Druids by more than two millennia. The persistent claim that Stonehenge is a Druidic site was put forward in 1666 by John Aubrey, the first historian to survey Stonehenge. Though the Stonehenge–Druid link is now rejected by most scholars, modern-day Druids still consider Stonehenge sacred and worship at the site during solstices.
It may be the most sophisticated prehistoric stone circle we know about, but is it the largest?
No. would be Avebury Henge, east of Bath. Like Stonehenge, Avebury’s three circles are circumscribed by a circular henge and were constructed gradually, over the course of many centuries.
