Overview: Explorer Levison Wood - famous for Walking the Nile, Walking the Himalayas and Walking the Americas - is taking on a new expedition in this four-part series: to cross the mighty Caucusus mountain range that lies between Russia and Iran. And as well as a new region of the world, Levison is taking a new approach to exploring: making his way by any means necessary. Travelling with the locals and living as they do, Levison's epic, 2,600-mile journey takes him through five countries, crossing the wild lands on the tense frontier between Europe and Asia and visiting some of the most fascinating and diverse people's on earth.