If you have time six months or so start by sailing to Naples/Pompeii go to Rome, Florence, Genoa, Turin, Milan, Verona, Padua, Venice, Parma, Bologna, San Marino, Pescara, Bari, Leuca, Gallipoli, Catania, Palermo, Syracuse then back to Naples and catch the boat home. If you have more tine go back to Rome.
If you have time six months or so start by sailing to Naples/Pompeii go to Rome, Florence, Genoa, Turin, Milan, Verona, Padua, Venice, Parma, Bologna, San Marino, Pescara, Bari, Leuca, Gallipoli, Catania, Palermo, Syracuse then back to Naples and catch the boat home. If you have more tine go back to Rome.