Prospection in a 1083 km2 region around Jenne and a 260 km2 region around Timbuktu was undertaken to establish settlement patterns and, from this, clues to the roots of urbanism in the Middle Niger. The Jenne survey, aided by accurate identification of settlements from aerial photography as established by randomized sampling of these sites, established the geomorphological circumstances of these settlements. Landforms and soils were evident from aerial photography but confirmed and elaborated by ground-truth analysis. The region was densely occupied from the last few centuries BC to AD 1100-1400, when most of the sites were abandoned. Many sites were clustered, and clustered sites were abandoned simultaneously. Lowland, clay soil sites were abandoned first, with the last sites abandoned being highland, sandier soil sites. This suggests that severe flooding contributed to site abandonment. The Timbuktu survey was undertaken to develop data to compare with the Jenne survey. Aerial photography was not as accurate, so sites were identified from ground survey. Two types of sites were noted and studied: dunefield sites, most of which were temporary sites (but some large exceptions lined the Wadi El-Ahmar east of Timbuktu), and floodplain sites which showed some considerable depth of deposits. In contrast, all Jenne sites were permanent. That Jenne and Timbuktu both have multiple hinterland sites suggest that these hinterland sites provided in some manner for the two urban centers, perhaps as communities of specialists that benefited from belonging to a separate local community in place of a mixed single-site urban siting.