With the Lattari Mountains looming above and the sparkling Mediterranean Sea below, Sorrento occupies an envious position on the rugged southwestern coast of Italy. Not only is the setting beautiful, but Sorrento is also the summertime gateway to the stunning scenery of the Amalfi Coast and the tony island of Capri.   We, however, were visiting in mid-January. And we were not sure what to expect when we boarded a bullet train on a frigid day in Florence. We were just hoping to unwind and...