Libations have long been associated with travel to far-flung coastlines. In 1609, when explorer Henry Hudson alit upon the shores of the river that today bears his name, he claimed to have encountered gnomes there who plied his crew with a potent brew that transformed them into beady-eyed little folks, too. During Prohibition, Americans flocked on European cruise ships to the Caribbean, where they could sip their fill of rum-based cocktails. Today, the world over, beaches are the locus of booze-filled frolics. Some beach drinks—minimalist concoctions like the Israeli favorite, arak and grapefruit—reflect summer's drive toward ease. Others, such as the Singapore Sling, are more elaborate, evoking the alleged exoticism of their native locales with tropical juices and spices, multiple liquors, and elaborate garnishes. But however it is made, a beachside cocktail sets the summer-vacation mood and cools the sun's heat.