From around the eighth century, camel caravans linked the gold fields of West Africa with the salt mines of the Sahara and the markets of North Africa, exchanging southern gold for northern salt, which was scarce and vital in the Sahel and at times traded weight for weight. West African gold became a principal source of bullion for the medieval Mediterranean and Islamic mints, while desert-edge entrepôts such as Sijilmasa, Audaghost and later Timbuktu grew as caravan termini. The trade carried Islam, scholarship and architectural ideas south across the desert. It financed the empires of Ghana, Mali and Songhai.
The gold-salt trade made the Sahara a connector rather than a barrier, bankrolling West African cities and tying African gold into the wider medieval world economy.