Scala/Art Resource, NY

Ambling along the portico of a sprawling bayside villa, vacationers gaze out at pleasure-boats adrift on the Bay of Naples, in this first-century A.D. fresco from Pompeii. Every summer upper-class Romans flocked from the hot, smelly, congested city to the bay’s resort towns, where they indulged liberally in sunshine, wine and romance—perhaps inventing the now-immortal idea of summer by the sea.