Several miles of The Ridgeway across the Berkshire Downs will be free of weekly invasion by recreational vehicles from now on.

More than 22 miles of the national trail stretching through Oxfordshire and West Berkshire have been classed as restricted byways, which is a new category of public right of way protected under the Government's Countryside and Rights of Way Act 2000.

These byways can be used by walkers, cyclists, horseriders and drivers of horse-drawn carriages, but not by off-road motorbikes and four-wheel drive vehicles.

The Act now applies to the whole country, and any public right of way previously termed a 'road used as a public path' - or in the historical classification of The Ridgeway as 'a green road' - is now a restricted byway.

The new laws mean almost 18 miles of The Ridgeway is now a protected byway.

The protected section stretches from south of the village of Bishopstone on the Wiltshire border near Swindon, all the way to the village of Compton in Berkshire, south of Didcot.

East of the Thames, more than four miles from Britwell Hill, near Watlington, to the A40 is also now a restricted byway.

The announcement of legal protection of the ancient drovers' road across the Downs comes six months after the Countryside Agency's new boss, Gerald Garbutt, donned his wellies and walked The Ridgeway with its National Trails Officer, representatives of county highways departments from across the region, walkers and other tail users, to see the damage being caused to its surface by traffic.

Last July, new powers were brought in to ban driving along the famous trail, which stretches between Ivinghoe in Buckinghamshire and Overton Hill near Avebury in Wiltshire, from the beginning of autumn until spring.

The land is prone to its most serious damage from two and four-wheel vehicles at this time.

Environmentalists, walkers and rambling groups have spent 20 years campaigning for better protection for the prehistoric track, sections of which have become badly churned up.

National trails officer Margaret Caddick said: "Our team will be changing signage on The Ridgeway this summer to make sure everyone is clear about these new sections of restricted byway.

"Information will also be updated to include advice on restricted byways for all users of the trail to inform them of where they can legally go, and to whom they should report any problems."

Off-road use of The Ridgeway will now be allowed on just 17 of the 87 miles of the route on byway sections in Wiltshire and West Berkshire, mostly from April to October only, and on a very short section in Buckinghamshire.