Terrain difficulty as a factor in raw material procurement in the middle palaeolithic of France

The interpretation of stone tool assemblages is difficult. How can provisioning choices, travel, and technological organization, when combined with the vagaries of use, discard, deposition, and preservation, be identified through material remains? The choice of lithic raw material sources in the past depended on many factors. The distance from source to site, often mentioned in archaeological studies, can be misleading if simple distance is measured as if the world is a flat sheet extending in all directions. The transportation of raw materials requires physical effort, and effort expenditure depends not only on distance but also on topography, so the choice of a raw material in the past may have been influenced by the relative terrain difficulty around different sources. Calculation of the energy required to walk from several lithic sources to two Middle Palaeolithic archaeological sites in southern France, when contrasted with the use of the raw materials from each source, demonstrates that terrain difficulty needs to be taken into account to understand past behavior.