A new book co-written by Maria Wheatley from Marlborough and Busty Taylor from Andover claims they can prove that Avebury did have an ancient solstice connection.

It has long been known that Stonehenge was built more than 4,500 years ago to worship the summer solstice.

Until now Avebury has always been an enigma and archaeologists and other researchers have been baffled by its purpose.

However, in their book Avebury, Sun, Moon and Earth, Ms Wheatley and Mr Taylor claim they have proof that the stone circle was built to worship the winter solstice in December.

They have peeled away layers of time to visualise the monument as it was when first erected some 2,500 to 3,000 years BC and its ancient setting.

Their research showed that 200 years ago one of the earth banks was extended when the turnpike road through Avebury was built.

It centres around one stone known as the Devil’s Chair which has a ledge on which tens of thousands of tourists have sat.

Until now, claim the writers, no-one in modern times appreciated the significance of the Devil’s Chair because of relatively modern changes to the surrounding topography.

Ms Wheatley, 44, who is a part-time lecturer at Swindon College, said: “About 200 years ago the bank was extended to create a toll road.

“In its original position it was about 37 feet back which made a big difference if anyone sat in the Devil’s Chair because before the bank was extended they would have had a clear view of the horizon at the winter solstice.”

Ms Wheatley has lived in Marlborough for about 14 years and been interested in ancient sites and pre history for about 20 years.

Ms Wheatley and Mr Taylor claim they have discovered “one of Avebury’s best kept secrets.”

She said: “Within the stone circle there was once a spectacular solar alignment which was closely associated with the Devil’s Chair.”

Even with the raised bank partly obstructing the view she said it was still possible to get glimpses of the sun rising over the horizon at the solstice.

The book costs £4.99 and is available at the Henge Shop in Avebury or the Tourist Information desk at Marlborough library.