Travel: Call of the World

Come spring, and the Call of the World sounds across the land. Never before have the multitudes been quite so willing—or so able—to respond.

More than 15 million Americans went abroad in 1966, and this year that figure may go up by as much as another 2,000,000. Why now? Says Travel Guide Temple Fielding: "The big story this season is the enormous increase in mass—v. class—tourism." Adds San Francisco Travel Agent Boyan Ribnikar: "With those group air fares, how can you afford to stay home?"

Indeed, the main reasons for the big summer...