“Thirty years ago, Medellín was the most violent, the most dangerous city in the world. Nobody wanted to go there, not even Colombians,” says Daniel Carvalho, the urban planner who launched street-art and hip-hop programs to make the notorious Comuna 13 district attractive to visitors and locals (and keep give young people something to do other than joining gangs). Now officials from Paris are consulting him on similar ideas for the French capital’s poorest banlieues. – The Observer (UK)