 They traded in ivory, furs and feathers with the Indian Ocean coast for goods such as glass beads and cotton clothes.The majority of these prehistoric Bakalanga villages have been discovered in Botswana and Zimbabwe in areas close to major rivers and were usually built on terraced hilltops with stone walls built around them.The Kalanga are linked to such early African States as Mapungubgwe, Khami, and the Rozvi Empire.