Watch the report by ITV Meridian's Cary Johnston
The Newbury Bypass was built 25 years ago this month, and was one of the most controversial road building programmes in the Thames Valley.
It cost more than £100 million to construct and was designed to take busy traffic away from the town.
The plan was to construct a new road around Newbury, which had become a notorious traffic bottle neck. But that meant cutting through areas of countryside, which the protestors were determined to protect.
Environmentalists protesting the site built 35 camps high in the trees on the route, and say it destroyed a beautiful area of countryside.
One of the most recognisable protestors was Daniel Hooper, known as Swampy. He tried to prevent the trees being destroyed by living in them.
He said: "We were trying to stop the diggers and bulldozers from working and they were trying to chainsaw the trees down. People ended up climbing up them and eventually building tree houses and ropes between them."
Daniel is still involved with protests and has been campaigning against the route of the HS2 high speed rail project, which cuts through the countryside of Aylesbury Vale.
Daniel Hooper, Environmental protestor:
Other campaigners say the Bypass paved the way for greater awareness of the need to protect the environment, including the challenges of climate change.
Adrian Forster-Fletcher, Newbury Friends of the Earth, said The Newbury Bypass shows the importance of public transport.
He said: "We need more school buses and more cycle paths. We need to get people out of their cars onto other forms of transport. That way we will fix the problem for the long term, not just the short."
The Newbury Bypass was eventually built, despite an extra £30 million being spent on security staff, and another £5 million on policing.
Steve Rowsell was in charge of construction for the Highways Agency when the road was built. He says it has greatly benefited the local community and wider economy.
He said: "Our overall objective was to build a road which blended in to the countryside and minimize the environmental impact. It's a fundamental role that the bypass plays in supporting the United Kingdom economy."
Steve Rowsell, Former Project Manager, Newbury Bypass:
They're very extensive memories and although it was 25 years ago this year that work started, they're still very fresh in my mind because it was quite shocking some of the scenes.
The legacy of the Bypass continues, with the present-day Government pushing ahead with a £27 billion road building programme and continued support for the HS2 fast speed railway project.