Volunteers cleared two ancient monuments of vegetation to make them visible again.
The project uncovered the remains of a medieval fortification at Cams Hill on the outskirts of Malmesbury and medieval earthen terraces (lynchets) at Southmill Hill in Amesbury, Wiltshire.
Historic England said the vegetation was damaging the monuments.
Volunteer Frances Matthews said: “I have wanted to see these lynchings cleared of the bush for years.
“It’s very rewarding to help achieve that,” she added.
The work was carried out as part of the Historic Monuments England Management Programme, which aims to improve the status of sites on the National Register of Danger.
Wiltshire is home to some of England’s most important ancient sites, a large number of which are protected by law because of their national importance.
However, more than 100 sites are at risk of being lost.
The project was funded by the Archaeological Service of Historic England and Wiltshire Council.
Volunteers included people from the Friends of Ancient Monuments, Wessex Council for British Archaeology, Amesbury Scouts and the Athelstan Museum in Malmesbury.
Historic England explained that the medieval fortification on Cam’s Hill has never been archaeologically investigated but is believed to have been built by Robert of Gloucester during his siege of Malmesbury in 1139.
After clearing, the monument is visible from the nearby path.
Amesbury’s medieval lynchets were once prominent landscape features to the south of the town.
But the field terraces, created by historical plowing over hundreds of years, began to disappear under shrubs and trees.
Works on the territory will continue until 2025.
Nick Croxon, Heritage at Risk Projects Officer at Historic England, said: “We are delighted to be able to fund this important project and we are delighted that so many members of the local community have come together to help look after these important and special places for the benefit of people both now and in the future.’
Roland Smith, Wiltshire Council’s Assistant District Archaeologist, added: “It was great to help with the conservation of two of Wiltshire’s archaeological sites and to see local volunteers get involved with such enthusiasm and enjoyment.”
Further work is planned for this autumn, where there will be more volunteering opportunities for local residents.