An improved algorithm for cost-surface allocation analyses: the case-study of the Bradano Valley (Basilicata, Italy)

A Thiessen polygons model allows an ideal scheme of the territories controlled by archaeological settlements, but it works on a plain and abstract geographic space. A more sophisticated approach uses cumulative costsurface maps to associate a portion of physical space to each settlement. This analysis can take into account the morphology of the territory and elements such as natural obstacles, but it starts from the assumption that each settlement has the same importance. In this paper, a new tool for creating cost-surface allocation maps is presented: in order to obtain more sophisticated and accurate models, this tool introduces the algorithm parameters that are dependent on attributes of the starting sites layer. The tool has been employed in the ancient settlements of the Bradano Valley (Basilicata, Italy).