Ethnographic and technological observations of iron smelting among the Haya people of northwestern Tanzania during 1976 and 1979 have contributed important new evidence for a technologically advanced culture in East-Central Africa. The ethnoarchaeology of Haya iron working shows that the Haya practiced an iron-smelting technology that employed preheating of the air blast -- a highly efficient technique -- and formed a massive steel altogether different from that known in the European tradition of iron production. Excavations in 1977 at the KM2 site near Kemondo Bay west of Lake Victoria in Kagera Region, Tanzania, provided abundant evidence for an ancient technology, dating to the first six centuries AD, that shared many similarities to the living iron-smelting technology. Excavations during 1978-1979 at the KM3 site, also located near Kemondo Bay, yielded physical evidence for the antiquity of the preheated process and provided definitive proof for a technology similar to the process in historical times. These discoveries affirm that one of the most advanced technologies in the ancient world developed in Africa independent of European influence. -- AATA