Raw material procurement at Boila Rockshelter, Epirus, as an indicator of hunter-gatherer mobility in Greece during the Late Upper Palaeolithic and Early Mesolithic

•Rare earth elements help link sites with potential geological outcrops.•Decline in non-local raw materials suggest reduced mobility during the Mesolithic.•Growth in microburin technique linked to increases in backed points and geometrics.•Palaeolithic to Mesolithic transition marked by changes in technology and mobility. Mobility represents one of the most important behavioural strategies of the Palaeolithic and Mesolithic, allowing groups to organise their use of landscapes by positioning themselves close to resources, as well as to regulate group size and social networks. One way of measuring the scale of this mobility is through the transport of lithic raw materials in the form of cores and finished artefacts. This paper aims to investigate settlement and mobility in Greece during the Late Upper Palaeolithic to Early Mesolithic transition, by using chipped stone technology and raw material transport as an index for wider subsistence and settlement changes associated with the Early Holocene. We take as a case study the Boila Rockshelter, located in the Voidomatis Basin in the rugged uplands of the Tymphi Massif, part of the Pindus Mountains in northwestern Greece. Typological analysis of almost two-thirds of the Boila chipped stone assemblage was carried out, along with geochemical trace element analysis on chert samples from the site, as well as limestone exposures in the local area and further afield. The geochemical analysis was focused on rare earth and other elements, with the results from Boila and the geological samples then compared. These confirmed that the majority of the chert used at Boila was originally derived from outcrops within the Vikos Gorge and Voidomatis River Valley, with the best pieces from approximately 10 km to the southeast of the site. Abrasion on the surfaces of these indicates that the majority of pieces used at Boila were collected from secondary fluvial deposits, such as those immediately below the site. In contrast, the geochemical results suggested that the reddish-brown varieties which were recovered at low frequency at Boila were probably collected from deposits located further towards the south. Synthesis of the results from the chipped stone and geochemical analyses suggested that during the Early Holocene at Boila, there was a change in the composition of the retouched tool assemblage. Backed bladelets continued to be made, but they were added to by increasing numbers of backed points and geometrics, along with a s