Although protests against the M3 had been ongoing since the early 1970s, the protest-action on top of the down, described in 1994 as the most controversial British motorway project ever to start construction,[1] attracted a wider range of classes of people than had previously been the case, and caused a violent clash with onsite security officers.

[2] The down's 142-metre (466 ft) summit, known as Deacon Hill, is towards the north-eastern edge of the area which is renowned for its dramatic rolling scenery and ecologically rich grassland.

St Catherine's Hill, in the centre of the down has been identified as a human settlement more than 3,000 years ago and pre-dates the foundation of Winchester.

[6] In 1675, John Ogilby noted that the main coaching route from London to Southampton ran over the top of the down, going directly from Alresford to Twyford, avoiding Winchester.

In the 1930s, a by-pass was planned to the east of the city, passing immediately west of St. Catherine's Hill,[14] opening to traffic on 1 February 1940.

[15] Construction of this had been controversial as it affected the Itchen Valley and offered only a partial solution to congestion, with some people calling instead for a by-pass to the north and west of Winchester.

[16] As a 1930s road construction project, the bypass was built to then-contemporary standards, including at-grade crossings at Bar End and at Hockley.

[20] At this point, the option of going over or through Twyford Down had not been considered, and the alignment of the proposed six-lane M3 motorway (three lines in each direction) was to run through the Itchen valley roughly west of the existing four-lane bypass.

[23] Morgan-Giles argued in Parliament to support the scheme, pointing out that Winchester and the Down had been cut off since construction of the old bypass anyway, and growth of Southampton Docks meant that improved links from London and the Midlands would become increasingly essential.

[24] In 1981, Kenneth Clarke, then the Parliamentary Secretary for Transport, stated that, since the route of the M3 was then fixed as far as Bar End, to the north of St. Catherine's Hill, that its route from there to Compton would undergo a fresh study,[25] specifically stating that the Winchester Bypass should continue to be operational during construction of any new road, and that environmental matters were a key concern.

[19] In March 1992, two travellers pitched a camp on the down, and discovered from local ramblers about the Bar End to Compton contract, meaning the land they were sitting on would soon be excavated.

David Croker, who had become head of the protest group Twyford Down Association, said they "had come to depend on the European Commission so we're very disappointed.

"[34] The principal arguments of the protesters were their concern about making wildlife species, such as the Chalkhill Blue butterfly, extinct, putting a highly visible scar on the landscape, and that they believed the new motorway would not adequately resolve traffic problems.

[1] Another protester, according to a report by local MP John Denham, was strangled by officers and left unconscious on top of the Down for 30 minutes.

[1] Maggie Lambert, then a mature photography student, took numerous photographs of the protest, and challenged an injunction which suggested she had been involved with direct action.

[1] Protester Rebecca Lush of the Donga Tribe, who had stayed on the down from September to the night of eviction, later claimed "It was a horrific experience and very violent.

"[37] In March 1993, Kenneth Carlisle, then Minister for Roads and Traffic, refused to order an inquiry into any wrongdoing or excessive force by security officers, stating it was a matter for the police.

[27] Replacing the bypass also reduced traffic volumes from the village of Twyford and removed the road that separated St. Catherine's Hill from the city.

In 1994, a government committee concluded that building more roads would only encourage more traffic, and that the way to ease congestion and pollution was to take measures to control car use rather than accommodate more.

[42][43] In 2000, campaigners mounted legal action to preserve an area of grassland created on the route of the old A33 Winchester bypass in mitigation of the land lost to the motorway which was threatened by a Park and Ride site.

[47] Also in that year, veterans of a Twyford Down protest threatened a new campaign of direct action in response to 200 new road-building proposals in the government's recently unveiled ten-year transport plan.