Experts discover huge stone circle in britain ten times the size of st

Historians believe Marden Henge in Wiltshire is the largest prehistoric circular monument in Britain and could be an "archaeological treasure-chest". Very little is known about the

now-collapsed 45ft high moat-surrounded mound because none of its original stones have survived. However it is thought that it could have been similar to world-famous heritage site

Stonehenge, only much larger.  Now 80 archaeologists from around the world have descended on the site for a three-year, £1million dig in a bid to unlock its prehistoric mysteries.  It is

believed the huge monument may have been part of a network of huge stone circles in the area, which also included Stonehenge and the Avebury stone circles.  Archaeologists' interest in

the site was rekindled four years ago when experts discovered an ancient sauna at the site, which is thought to be the oldest building in Britain.  It has been sugested sauna users might

even have helped haul the huge stones upright at Stonehenge, or that the different monuments might have been used by competing communities.  Dr Jim Leary, who led the 2010 dig which

uncovered the sauna, said: "I have been waiting five years to come back to this site. "It is right in the middle of Avebury and Stonehenge, which are probably the most famous

prehistoric sites in the world, but nobody has ever researched it properly. "I think understanding the Vale will give us a greater understanding of Avebury and Stonehenge. "This

excavation is the beginning of a new chapter in the story of Stonehenge and its surrounds. "The Vale of Pewsey is a relatively untouched archaeological treasure-chest under the shadow

of one of the wonders of the world."  The 4,000-year-old Marden Henge is the largest Neolithic henge enclosure in the UK and sits between the World Heritage sites of Avebury and

Stonehenge. Roughly oval in shape and covering 35 acres, it was enclosed by a bank and a ditch, which would have been filled with water before it all collapsed in 1807. In 2010 the

39-year-old directed excavations at Marden Henge and found a pre-ritual "sweat room" at the site. Ever since University of Reading academic Dr Leary has been consulting with

funders, experts and land owners to negotiate the three-year dig which began last week. Over the next three summers a team of 80 students and archaeologists will explore a series of trenches

and five 100ft by 100ft shallow sites. Excavations this summer will focus on the surface of the Neolithic building he originally uncovered. Dr Leary said: "Why Stonehenge was built

remains a mystery.  "How the giant stones were transported almost defy belief. "It must have been an astonishing, perhaps frightening, sight. "Using the latest survey,

excavation and scientific techniques, the project will reveal priceless insight into the lives of those who witnessed its construction. "Marden Henge is located on a line which connects

Stonehenge and Avebury. "This poses some fascinating questions. "Were the three monuments competing against each other? Or were they used by the same communities but for different

occasions and ceremonies? We hope to find out."  The project is a collaboration with Historic England, the Arts and Humanities Research Council and Wiltshire Museum. Duncan Wilson,

Historic England chief executive, said: "Bigger than Avebury, ten times the size of Stonehenge and half way between the Stonehenge and Avebury World Heritage Sites, comparatively little

is known about this fascinating and ancient landscape.  "The work will help Historic England focus on identifying sites for protection and improved management, as well as adding a new

dimension to our understanding of this important archaeological environment."