GIS-Based Least-Cost Path Analysis in Eswatini’s Stone Age Archaeology

Bader et al. "Decoding hunter-gatherer-knowledge and selective choice of lithic raw materials during the Middle and Later Stone Age in Eswatini" (Journal of Archaeological Science 180, 2023, 106002) employs GIS-based least-cost path analysis to elucidate the mobility patterns of Middle and Later Stone Age hunter-gatherers in Eswatini, focusing on their strategic transport of lithic materials. By integrating terrain, slope, and resource distribution data, the analysis maps optimal routes between raw material outcrops, notably red jasper and green chalcedony and demonstrates that hunter-gatherers transported them over distances ranging from 20 to as much as 100 kilometers. The research clarifies that larger clasts (62–256 mm), ideal for knapping, were not effectively transported by fluvial processes. Instead, humans deliberately carried these clasts from primary outcrops.

An interesting use of the technique which will have more uses in the study of  Neolithic Wessex, I'm sure. As does the innate drive in prehistory to transport lithics. 

 Least cost path analysis indicating the optimal transport routes between raw material outcrops and archaeological sites.

Gregor D. Bader, Christian Sommer, Jörg Linstädter, Dineo P. Masia, Matthias A. Blessing, Bob Forrester, Brandi L. MacDonald,

Decoding hunter-gatherer-knowledge and selective choice of lithic raw materials during the Middle and Later Stone Age in Eswatini, Journal of Archaeological Science, Volume 180, 2025, 106302, ISSN 0305-4403,

https://doi.org/10.1016/j.jas.2025.106302.

(https://www.sciencedirect.com/science/article/pii/S0305440325001517)

Abstract: Reconstructing past movement and mobility patterns requires a landscape-scale approach with knowledge of potential raw material sources and, ideally, multiple archaeological sites. Building on legacy collections in the Lobamba Museum in Eswatini and the identification of primary lithic raw material outcrops through landscape survey, we can provide scenarios of raw material provisioning for hunter-gatherers in Eswatini over the past 40 000 years. We used Neutron Activation Analysis (NAA) to refine the terminology as the three ‘chert’ varieties from the archaeological sites Hlalakahle, Siphiso, Sibebe and Nkambeni are more precisely described as red jasper, green chalcedony and black chert. We were able to identify the primary outcrops for both red jasper and the green chalcedony. Using a least cost path (LCP) analysis together with hydrological and geomorphometric estimates of clast transport in relevant rivers, we reconstructed potential transportation routes of raw material and infer likely provisioning scenarios. During the final Middle Stone Age (MSA), red jasper occurs rarely or is absent in archaeological assemblages, while green chalcedony and other chert variants are frequently observed. This is despite the source of red jasper occurring near the green chalcedony outcrop. During the Later Stone Age (LSA), the red jasper, and a red chert variant of unknown provenance appear more frequently, indicating different raw material provisioning choices.