NATAL, Brazil (AP) — Long before the U.S. soccer team arrived in this balmy coastal city for the World Cup, another group of uniformed Americans came through. They turned this isolated part of northeast Brazil — the closest point in the Americas to Africa — into a World War II boomtown.

President Franklin Roosevelt dubbed Natal the “Trampoline to Victory,” for keeping allied troops in Africa supplied. During part of the war, Natal was the busiest airport in the world, with flights taking off and landing every three minutes.