EASIDE destinations have existed since antiquity—Emperor Tiberius lived for years on Capri and expanded his empire from the small, rocky island—but the act of sitting on a beach for pleasure didn’t exist until the 18th century. Water, the great, roiling unknown, was there to be feared. It was synonymous with death. The mythical Underworld was surrounded by a series of rivers, each one given a more depressing meaning than the last: the Styx (the river of unbreakable oath), the Cocytus (the river of lamentation), the Acheron (the river
