Bikers and walkers are being urged to stick to designated paths through heather moorland in Denbighshire to prevent more damage to the landscape.
The council has launched a campaign to stop further deterioration around rural Llandegla and Eglwyseg which is used as a route to Llangollen.
It said people straying off routes was damaging the area and affecting wildlife such as nesting birds.
The mountain bike centre at Llandegla is backing the campaign.
Councillor Tony Thomas, cabinet member for the environment, said: "This landscape is unique, but it is also fragile.
"We want to protect this unique landscape and prevent any further damage to the paths, the heather moorland and the wildlife that has made the moorland their home."
Ride North Wales and Oneplanet Adventure, which runs the mountain bike centre, are involved in the campaign, which encourages cyclists and other users to stick to official routes.