This month's programme covers the OMM - the original mountain marathon - in Highland Perthshire. The first multi-day event of its kind and to many competitors, still the best. A test of endurance, navigation and willpower where competitors need to carry everything they need on their back.

It's over 150 years since climbing developed as a sport and in that time Britain's great crags have been thoroughly explored. In their search for bold new routes, two of Scotland's best rock athletes, Dave MacLeod and Alan Cassidy, travel south of the Border to the heart of the English climbing scene.