Salt Making in the Central SaharaFor centuries camel caravans transported salt south across the Sahara to the great West African kingdoms, where it was exchanged for gold. Here at Tegguida-n-Tessum, Niger, in the central Sahara, salt is still collected by pouring spring water into small pools dug out of the saline soil. The water leaches out the salt before evaporating in the desert sun, leaving deposits of pure salt behind, which are then shaped into blocks for transport. (Afrique Photo, Cliché Naud/Visual Connection Archive)