Three eminent historians - Dan Snow, Ruth Scurr and Tom Holland - are uniting with the Stonehenge Alliance to oppose plans by the Department for Transport, for a £2bn road engineering project in the Stonehenge World Heritage Site.

Dan Snow and Tom Holland will be making their point when they visit the Stonehenge World Heritage landscape with Alliance members today.

The Government announced in December 2014 revived plans to dual the A303 trunk road across the Stonehenge World Heritage Site including a tunnel of up to 2.9km in length, leaving 1.6km or more of above ground road widening and cuttings on the surface of the site.

The £2 billion scheme was welcomed by English Heritage, which looks after the stone circle, and the National Trust, which owns much of the land in the wider World Heritage Site. The heritage groups said the tunnel would make the setting of the stones more tranquil, give the public greater access to the wider prehistoric landscape and improve the environment for wildlife.

But the Stonehenge Alliance has written to Secretary of State for Transport, Patrick McLoughlinover, over its concerns that the tunnel being considered for Stonehenge is too short - calling for a 4.5km tunnel instead - and would damage the site. 

Mr Snow, broadcaster and president of the Council for British Archaeology, said "Around the world we see pictures of our fellow humans smashing the treasures of the past and count ourselves lucky that we live in a country which values its rich history and appreciates what it offers modern Britain.

"Our heritage helps us understand ourselves, how we got here and where we are going.

"Of all our many treasures on these islands, none is more internationally revered than Stonehenge. We have recently started to realise that the standing stones are just a beginning, they sit at the heart of the world's most significant and best preserved Stone Age landscape.

"The Government's plans endanger this unique site. "

Broadcaster and award-winning classical historian Tom Holland said: “There is so much waiting to be learnt about how Stonehenge was built - if we decide, as a country, not to sacrifice it to road-building.

"The battle to save our most significant neolithic landscape is an unending one.”

Ruth Scurr, author of a biography of John Aubrey published this month, said "Previous generations worked hard to preserve Stonehenge.

"In the 17th century John Aubrey, member of the Royal Society and early archaeologist, surveyed the stones for posterity. He would have been horrified by the current proposal to widen the A303 with destructive effect on the surroundings of this important monument.”