“I don’t think I’ve ever seen it so busy!” declares my dad as we pull into the car park of Housesteads, which sits along Hadrian’s Wall, one of the best-preserved Roman forts in Britain. He’s right: the car park is rammed and the entrance to the site is unusually crowded. Tourists with backpacks sit on picnic benches eating cake from the cafe, while a dad reads aloud the noticeboards to his small children.
