Travel agencies specialising in perilous holidays are offering organised trips to war zones and even areas struck by natural or nuclear disasters. In Afghanistan, a group of tourists scale the mountains of Hindu-Kush, climbing 4,000m above sea level in order to ski down this one-of-a-kind slope; in Indonesia, plucky thrill-seekers climb Anak Krakatoa, an erupting volcano; and in Ukraine, adventurous tourists come from all over the globe to visit the dead city of Chernobyl, the site of the worst nuclear disaster in human history.