Since 2014 a plan has been under consideration to dig a nearly two mile tunnel through the Stonehenge World Heritage Site. From the Stonehenge Alliance website:
The Government proposes to widen the A303 trunk road to the south west. The 4-lane carriageway, tunnel, slip roads and trenches would cross the iconic Stonehenge World Heritage Site (WHS): a landscape that is considered “the most archaeologically significant land surface in Europe without parallel”. The whole Stonehenge landscape has an outstanding universal value that is of immense significance for all people for all time, and this transcends any consideration of sorting out a 21st century part-time traffic jam.
The whole site, extending to beyond the horizons around the famous stones themselves, is c. 5.4 km across. All of it makes up a “huge ancient complex” that holds many secrets yet to be discovered. Yet the proposal is for a 2.9km (1.8 mile) tunnel. It would result in at least 1.6 km of above-ground 21st-century road engineering within the WHS.
The lifespan of concrete is remarkably short. Modern reinforced concrete needs repairs after only fifty years. In the fullness of time the decay of the tunnel will destabilize the landscape around Stonehenge. Assuming this generation wishes to bequeath the monument to posterity the risk is unacceptable. Please help Stonehenge Alliance protect the site.