Every generation has worried that travel frontiers are disappearing

"D.H. Lawrence, in a letter written early in the last century, complained, "I feel sometimes, I shall go mad, because there is no where to go, no 'new world.'" In Tristes Tropiques (alternately—and tellingly—titled A World on the Wane ), published in 1955, Claude Levi-Strauss wrote, "There was a time when traveling brought the traveler...