Even after 4,500 years, Stonehenge is bathed in mystery. Was it a temple? An observatory? Something else?
Mike Parker Pearson, an archeologist at the University of Sheffield, thinks he has a new answer. After eight years of excavation, he argues that Stonehenge was just one part of a great religious complex, built by Neolithic people in Britain who did not yet have writing or the wheel.
Newly-completed radio-carbon dating suggests that Stonehenge may have been used to bury cremated remains for 500 years, Parker Pearson said.
Two miles away from the famous circle of Stonehenge, he says there is evidence of a primitive town — primitive but remarkably large for 2,500 B.C. It would have had room for more than a thousand people.
What's more, there are signs nearby of a second circle — a virtual twin, except that it was made of wood.
"It surprised us, he said. "It actually looks far more like Stonehenge in wood than we'd ever appreciated."
"The two circles have very profound architectural similarities, even if they're made out of different materials," said Julian Thomas of the University of Manchester, who has been working with Parker Pearson.
Why would there be two great circles so close to each other, not far from the river Avon in southern England?
Parker Pearson theorizes that the wooden circle was a celebration of life and perhaps fertility, while Stonehenge — the only remaining part of the complex — would have been a monument to death or the afterlife.
"Why might it have been important for them to have had one in wood, one in stone?" said Parker Pearson. "I think it has to do with the materials and what it meant to peoples' lives.
"Wood is something that doesn't last forever, just as our own lives won't last forever. But stone, that's going to be there for eternity."
Cremated remains of some 240 people have been found in the last 75 years at Stonehenge, on the outer perimeter of the stone circle. Parker Pearson and his team were able to do radio-carbon dating of some of them, which led to today's conclusion that cremations at Stonehenge could have taken place over a period of half a millenium.
Until now, archeologists had thought Stonehenge was actively used for burials for only about a century. The carbon dating techniques used on burnt remains have only been practical for a few years.
Parker Pearson's work was funded in part by National Geographic, which has put Stonehenge on the cover of its current issue, and is running a special on its cable channel. ABC News has a content partnership with National Geographic.
There are other archeologists who disagree with Parker Pearson's theory. Some of them suggest Stonehenge, with its blue stones dragged overland from miles away, may instead have had something to do with healing.
"I don't see much evidence of that," said Parker Pearson. He says not many of the burnt bones show signs of primitive attempts at curing illnesses. "Healing may have been a part of it, but a small one."
"But it's possible for competing theories both to be true," said Thomas, his colleague. "We archeologists love a good debate."