This abandoned East African city once controlled the medieval gold trade

During its medieval heyday, Kilwa was the principal port in a string of coastal trading cities that formed along what became known as the Swahili Coast Convinced of the "Inferiority" of Africans to non-Africans, European scholars, like the British explorer Richard Burton, who visited Kilwa in 1859, believed that the indigenous African culture was incapable of developing stone-built cities Kilwa and other trading cities of the Swahili coast grew out of a complex mix of influences, starting on a strong foundation of local East African tradition.

As an aid to dating the various phases of Kilwa's history, Chittick relied heavily on the Kilwa Chronicle, a medieval genealogy of the city state's kings Kilwa's rise to power dawned with the founding of the Kilwa sultanate Dhows, the sailing ships characteristic of East Africa, set out from Kilwa and Sofala laden with gold, grain, wood, and ivory.

Historical accounts say that Chinese naval explorer Zheng He traveled to the Kilwa Sultanate and the Swahili coast between 1405 and 1433 on his famous Seven Voyages. . Source