The saying goes that the Italian South begins with the first petrol station below Rome, and certainly there’s a radically different feel here. Green wooded hills give way to flat marshy land and harsh unyielding mountains that possess a poor, almost desperate, look in places – most travellers skate straight through en route to Naples. But the coast merits a more unhurried route south – its resorts, especially Terracina and Sperlonga, are fine places to take it easy after the rigours of the capital. And Ponza, a couple of hours offshore, is – out of high season, at least – one of Italy’s undiscovered treasures. Inland, too, there are rewarding points to head for: the day-trip towns of the Castelli Romani; the peaceful retreat of Subiaco, set amid glorious scenery; and Cassino and its nearby abbey of Montecassino, where some of the fiercest fighting of World War II took place.