Why is China restoring a British railway in Angola? Justin Rowlatt boards the Benguela Railway. A new generation is shaping the future of Afghanistan: Lyse Doucet finds out how. Just back in Russia, Steve Rosenberg considers the country's future. Annie Caulfield visits a Kenyan reptile sanctuary and discovers the role snakes play in the environment. And Christopher Landau explains why he's giving up journalism to pursue a more spiritual vocation.