Artist Anish Kapoor’s work has grown so large in recent years it could be mistaken for architecture. Now he’s been asked to produce some architecture. The city of Naples has asked Kapoor to “design a new underground station – a complex piece of infrastructure that is usually the preserve of architects and engineers. ‘They’re mad,’ he says. ‘It’s folly. They don’t know what they’ve let themselves in for. But it’s wonderful; I can’t imagine anything better than doing a tube station’.”