This small, narrow coral island a couple of miles off the mainland in the Mozambique Channel looks unimpressive from a distance. But for centuries it was one of the most important trading ports on Africa’s Swahili Coast. The Indian Ocean dhow flocked here to trade in gold, ivory, spices and slaves. An important Arab trader, Musa al Big, gave the island, and later the country, his name when the Portuguese Vasco da Gama sailed there at the end of the 15th century. The Portuguese held it long after the opening of the Suez Canal and the abolition of slavery starved its trade. Walk the narrow streets of its UNESCO-inscribed Stone Town, lined with uniform Swahili-styled houses. The Nossa Senhora de Baluarte church from 1522 is considered the oldest European building in the Southern Hemisphere. Fort São Sebastião was built in 1608 to fend off Dutch attacks. The 1610 Palace and Chapel of São Paulo is now a museum. The turquoise waters off the beaches are plied by lateen-rigged dhows that look identical to those that arrived in centuries past.