However, they are still worried about the proposal to link two byways, introducing a new route for vehicles close to Stonehenge after the tunnel is built. They are also calling for a 200m grass canopy at the entrance and exit of the tunnel.
They said: "This is a once in a generation opportunity to reunite this ancient landscape giving people the opportunity to tread pathways used by our ancestors who built the monuments, to visit and appreciate the monuments and to see and hear wildlife without the intrusion of traffic noise from the road."
But some historians warned that Stonehenge could have its World Heritage status taken away if the Government pushes ahead with the proposed works. Others have expressed concern about nearby sites, such as Blick Mead, which is the only place in Britain where human habitation can be traced back to 8,000BC.
In October, volunteers found preserved hoof prints of wild cattle, known as aurochs, near to where the proposed flyover would be built.
Professor Simon Jacques from Buckingham University, who led the excavation, told Sky News: "There is no excuse for this site to be totally neglected. I mean it is right next to the flyover and about 500 metres from the Eastern portal.
"People have known it has been there for a long time.
"Places like this are incredibly rare in the British Isles and anywhere in the world and we have essentially got a unique national archive.
"All of the organics that we have got on the site, imagine they're documents. Professor Simon Jacques from Buckingham University
"With what Highways England plans to do, with their eight metre high flyover, the water will be drained holding all those organisms and the site will in effect, it will be killed."
However, in nearby villages like Shrewton, which is blighted by traffic, some residents are keen for the tunnel to be built and have taken the law into their own hands.
Janice Hassett, who runs the Stonehenge Traffic Action Group, has been trained up by Wiltshire Police to help catch speeding drivers.
She said: "There are very few pavements in the high street and there are lots of elderly people, mothers with prams. The school is on the high street and it's very dangerous, especially on Friday and Saturday mornings".
Highways England has opened a consultation today which will run until April to gauge public opinion on the controversial matter. The group's chief excutive Jim O'Sullivan said: "These upgrades in the South West will improve millions of journeys.
"Each of these milestones in the region is evidence of Highways England delivering major infrastructure upgrades for the whole country."
The upgrades are funded by the Government's £15 billion investment into motorways and main A-roads across the country.