Off-roaders using illegal routes face fines of up to �20,000

Routes are provided by the National Park which can be used by bikes and vehicles legally.

But some people are ignoring the regulations and going off the routes, causing considerable damage to the landscape, and they could face �20,000 fines.

National Park bosses say it is a growing problem and have brought out a leaflet to advise off-roaders of the types of tracks they are allowed to use.

Those riders going off the recognised routes are breaking road traffic regulations and laws to protect valuable landscape.

The National Park has issued a leaflet detailing the official routes

One hillside, in particular, has become badly eroded because of bikes travelling up and down it, and the damage will get worse if used through the winter.

Paul Hawkins, of Exmoor National Park, said: "The back tyres are acting like a spade and digging up the vegetation.

"The hillside is the home for many different species.

"Not only that but this site is open for walking. There is the danger of someone meeting a motorcyclist completely unexpectedly."

Permanently damaged

Members of the Trail Riders Fellowship observe the rules and stick to the routes they are allowed on.

But one member, Mike Maddocks, said: "We all get tarred with the same brush.

"We are seen as the enemy and we don't want that.

"We would like to be seen as helping the Exmoor National Park and other authorities."