THE TEN Tors Challenge, the greatest annual adventure for young people over rough terrain in Britain, starts from Okehampton Camp tomorrow. At least half a dozen teams are taking part from Teignbridge, including Coombeshead College, Newton Abbot, Knowles Hill School, Newton Abbot, 1322 Newton Abbot Squadron ATC and scout groups from Bovey Tracey, Highweek, Ipplepen and Kingskerswell. Teams can opt to tackle a 35, 45 or 55-mile route. But all 2,400 participants in 400 teams, will have to camp out on the moor overnight. Brigadier Jolyon Jackson, Ten Tors director and the 43 Wessex Brigade Commander, told eventers: 'This is a weekend you will remember for the rest of your lives. 'You will pit yourselves against the rough terrain of Dartmoor, against the weather and experience real physical and mental pressure.' Possibly the most unusual entry this year are two pack ponies from the Dartmoor Pony Heritage Trust (DPHT). Golden Flame, an eight-year-old mare, and George, a colt foal under one year, will be helping a team from Milford Special Needs School, near Plymouth, in their Jubilee Challenge of 15 miles. Dru Butterfield, DPHT project officer, said that the ponies would be there to help motivate the team and take their mind off their own blistered feet. Milford students have been working with George and Golden Flame for several months. 'The ponies have displayed great gentleness despite the often enthusiastic approach some students have made,' she said.