The Welsh town of Hay-on-Wye has 1,600 residents – and thousands of people coming to its book festival. Its director explains why Hay is special: “I think we all have a special sense of place that defines what we do and how we do it. For Hay that’s the open green mountains and the dark skies, and it’s the fact that the town has 1,600 people and 28 bookshops. How many cities have that kind of wealth?” (Also: Survive by talking to other book fans.)