 In Scotland s Cairngorm National Park, tourists come to walk in the glens or climb the mountains, but few realize the park is classified as an Arctic landscape -- and an average of 30 tourists die here every year.  Host Bear Grylls shows how to navigate the region using ice formations and moss growth, and tests snow slopes for avalanche potential.  He uses moss to purify water and skins a red deer for shelter.  For food, he traps and cooks a rabbit. Bear crosses deep marshes that can swallow a man and uses fallen trees to cross ravines.