Campaigners have launched a High Court challenge to the government's decision to approve a £1.7bn road tunnel near Stonehenge.
Save Stonehenge World Heritage Site (SSWHS) has applied for judicial review of transport secretary Grant Shapps' decision to grant consent.
Mr Shapps approved the scheme in November, against the recommendations of planning officials.
Work on the two-mile (3.2km) tunnel on the A303 is set to begin in 2023.
Campaigners are worried that the work will have a detrimental impact on the wider Stonehenge world heritage site - which surrounds the ancient stone circle - and planning officials had said that the project could cause "permanent, irreversible harm".
A panel of expert inspectors recommended that consent should be withheld, but the Department for Transport disagreed and said: "On balance, the need case for the development, together with the other benefits identified, outweigh any harm."
SSWHS argue that the scheme is contrary to the Wiltshire Core Strategy and the requirements of the World Heritage Convention.
Tom Holland, president of the Stonehenge Alliance, said it was "hard to believe" that the scheme has been given the green light.
"The Planning Inspectorate, after a painstaking, six-month investigation, advised against them.
"Let us hope that the law can come to the rescue of a landscape that ranks as our most precious and sacred, and which the government - to its eternal shame - is set on handing over to the bulldozers."
The tunnel is part of a £1.7bn investment in the A303 between Amesbury and Berwick Down.
The road, which is a popular route for motorists travelling to and from the South West, is often severely congested on the single carriageway stretch near the stones.
Highways England says its plan will remove the sight and sound of traffic passing the site and cut journey times.
A spokesperson said: "We remain confident this scheme is the best solution for tackling a long-standing traffic bottleneck, improving journeys, bringing much needed relief to local communities and boosting the economy in the south west."
The Department for Transport said it could not comment further as the six week legal challenge period for the decision was still ongoing.