Campania is a region in South-Western Italy.
Public Transport: within Campania the public transport has a unified ticket system called Campania Unico. Tickets are organised in zones which means that with one ticket you can travel within one zone (usually defined by how long it takes , someone could try to explain better!), two or more. Included in this system are generally national trains (also to Paestum, the underground in Naples, the Funicolore in Naples, Cita buses along the Amalfi Coast, the Funicolore on Capri, the Circumvesuviana that goes also past Pompeii and Herculaneum but NOT ferries. The advantage is not only, that you can get tickets for different kind of vehicles, but you could also buy tickets in advance for areas where it is difficult to find a ticket office such as Paestum, as the tickets start to be valid once you stamped them. It is possibly also cheaper to buy a bunch of 'one zone' tickets than each time a new one. But careful: some tickets are locally bound (only in Naples, for example). If in doubt, ask when you buy your tickets.