In pine forests on the rugged foothills of north wales, enthusiasts of the occasionally bruising sport of mountain biking are being put through their paces. At the Coed-y-Brenin centre, some of the trails have been given names such as Captain Scarlet; Snap, Crackle and Pop and, alarmingly, the Rocky Horror Show, a boulder-strewn descent which had to be toned down when the toll of fallen riders began to soar.

The cultivated trails are designed to suit different abilities and levels of daring-do, with something for everyone. The 11,500-acre forest is clearly waymarked, so that cyclists never end up somewhere which is beyond their abilities. And you don’t need to keep getting off your bike to read a map.

Mountain biking is an outdoor adventure pursuit which is growing in popularity. Anyone can do it as long as they can ride a bicycle, but not everyone has access to terrain to do it safely or with adequate guidance. Given the combination of treacherous slopes and speed, if you don’t know what you’re doing the potential for disaster is considerable.

Dafydd Davies, of the Forestry Commission, is overseeing the creation of cycling adventure sites in Wales. The benefit of these areas is that they are safer, more environmentally-friendly (erosion is kept to a minimum) and there are no chances of getting tangled up with lorries, horse riders or ramblers.

Andy Green, of the Cyclists Touring Club, says that, more schools are keen to add cycling to their outdoor activity breaks.

“The evidence seems to be that the pursuit is growing in popularity with both schools and youth groups,” he says. At Coed-y-Brenin, the numbers have been steadily increasing: in 1994 thre were 14,000 visitors. Last year the figure had jumped to 120,000.

“There are trails to suit every rider,” says Mr Davies. “Some are technically difficult. Others are ideal for beginners. We wanted to make the trails exciting and challenging but as safe as possible.

“At first, we thought the centre would be popular with hard-core riders but we are finding it is proving accessible to a wide range of people of varying abilities.”

Bikes can be hired and there are guides for those who want them. It is used to young riders and school groups. A school in Somerset visits three or four times a year. Another in Hounslow, west London, uses it to give its city children a chance to let off steam in an unfamiliar mountain environment.

The Cyclists Touring Club says mountain bike centres are springing up all over the place, although Coed-y-Brenin remains one of the best. CTC is working to develop an accreditation scheme for standards of safety and instruction.

Coed-y-Brenin has 68 miles of marked trails which centre on three main thoroughfares and a short “dual descender” course, which is particularly popular with children because two bikes can race down at the same time over its jumps, bumps and curves.

Kati Owen, aged 11, is tackling the rigours of the sport for the first time. “This was fun,” she says. “I hope to be able to come back here again. It’s quite difficult at first but I enjoyed learning new skills.”

Coed-y-Brenin, Ganllwyd, Dolgellau, Gwynedd LL41 2HY Tel: 01341 440666.

Contact: Dafydd Roberts.

Bike hire pound;4 an hour, pound;14 a day. Guides around pound;30 a half day, for up to seven people.

For details of other mountain bike centres contact the Cyclists Touring Club, tel: 01483 471217.

For details about instruction, contact: the Cycling International School, tel: 01352 810373.