A field survey and Geographical Information Systems (GIS) based investigation of the archaeological landscape in the Niger River Valley, Republic of Benin

Abstract The Niger River Valley in the Republic of Benin is an archaeologically rich landscape, where hundreds of sites line the river’s tributaries. Before this doctoral research was conducted in the region, the landscape here was a terra-incognita. In order to archaeologically investigate the area, several methods were used consisting of a field walking survey, and the use of satellite remote sensing and Geographical Information Systems (GIS). An integration of these methods, which are commonly used in research out of Africa, showed the diverse nature of archaeology in this region. The field walking survey revealed the position of over 300 sites and around 50,000 material culture artefacts, comprising of mainly ceramic vessel sherds. The field survey was undertaken over 45 days and covered a total area of 25km2 within four geographical zones in the study area. A comprehensive gazetteer was produced from the data collected. Remote sensing methods that manipulate multispectral satellite imagery were used to identify sites from the air, because the archaeology of this region is not visible from standard air photographs. The mapping of sites using GIS facilitated in establishing fundamental landscape patterns, which helped substantiate theories surrounding West African urbanism and human-environment interactions. The results conveyed that settlements in this region favour areas where water is available, mainly close to perennial and ephemeral fluvial systems. Furthermore, the archaeological sites identified display strong evidence of spatial clustering, which has been shown in other West African contexts to be indicative of early urbanisation.