Glentress is south of Edinburgh near Peebles, it was set up by the forestry commision as part of the seven stanes project around the borders, the hardest route (V-Trail) was sponsored by Helly Hansen and its 30k's of pure mtb heaven, prob one of the hardest mtb courses i have done, only for the confident or experienced i would say. They also have a mtb shop and brilliant cafe as well as numerous other routes, would live there if i could!