4,000-year-old 'Seahenge' in UK was built to 'extend summer,' archaeologist suggests

A mysterious Bronze Age wooden circle known as "Seahenge" on England's east coast was built more than 4,000 years ago in an effort to bring back warmer weather during an extreme cold spell, a new study suggests.

The theory is a new attempt to explain the buried structure — a rough circle about 25 feet (7.5 meters) across, made from 55 split oak trunks surrounding a "horseshoe" of five larger oak posts around a large inverted oak stump — that was controversially dug up and moved into a museum in 1999.

Other researchers have suggested it was built to commemorate an important individual who had died, or that it was a place for "sky burials," where the dead would be pecked by carrion-eating birds.

But the idea that Seahenge and another circle of buried timbers found beside it were built to "extend summer" fits with what's known about the climate at the time, said David Nance, an archaeologist at the University of Aberdeen in the United Kingdom and the author of the new study. 

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The construction took place during "a prolonged period of decreased atmospheric temperatures and severe winters and in late springs placing these early coastal societies under stress," he said in a statement. "It seems most likely that these monuments had the common intention to end this existential threat."

Nance detailed his study of the two Seahenge structures — known formally as Holme I and Holme II — in a research paper published April 2 in GeoJournal.