Every year I look forward to January. In Europe, it’s the easiest time to avoid crowds. One of my favorite winter destinations is Venice. On a recent January visit, we had Peggy Guggenheim’s ordinarily claustrophobic palazzo almost entirely to ourselves — and we battled the chill with frequent breaks for cicchetti and grappa. I’ve had equally delightful winter visits to Florence, Barcelona, Lisbon and Sicily, all of which tend to be quite mild even in the depths of winter.