Set in Stone? Exploring Petroglyphs in the Context of Early Complex Societies in Southern Costa Rica

This project investigates the spatial and social dimensions of prehistoric petroglyphs (artistically carved boulders) in southern Costa Rica, exploring their placement within the archaeological landscape and their relationships to settlements. Its main research question is: How are ancient petroglyphs embedded within the wider archaeological landscape and how may their spatial relation to nearby sites help us shed light on their function and significance? Petroglyphs are highly visible and present within the landscape, yet their functions are quite underexplored, especially considering their widespread distribution across the Central Americas and the amount of effort that went into creating them. Their study and recording are urgent, as the climate, vandalism, and increasing clearing projects are causing their rapid deterioration and destruction. Costa Rica features thousands of petroglyphs with anthropomorphic, zoomorphic, and geometric motifs. Their forms range from barrels, spheres, and pillars to largely unworked boulders. Some depict concrete scenes, while others present abstract images that remain difficult to interpret. Research has suggested various functions for these petroglyphs, such as community maps or indicators of sociopolitical influence. Studying them can provide insights into the emergence of complex societies and social hierarchies, as carving hard stone and transporting boulders across the landscape required significant time and labour. However, the relationship between petroglyphs and social complexity remains underexplored. Most research has focused on interpreting styles and motifs, neglecting their broader archaeological context. The deliberate placement of petroglyphs in public arenas, e.g. tributaries, transit or residential areas, indicates wider communal functions yet to be understood. Frequently located near bodies of water, they are considered to hold spiritual significance for ancient Costa Rican societies. In some areas, petroglyphs appear linked to elite sculpture and architecture, in others, they are found close to burials. The variety in sizes, contexts, and placements within and beyond settlements suggests a range of social purposes, yet systematic studies of these patterns are nonexistent. To date, there is a significant lack of research on regional patterns, spatial organisation, and the role of stoneworking traditions in Costa Rica and the broader Central American context. This project seeks to address these gaps and advance our understanding of petroglyphs within ancient societies. It examines the location, motifs, manufacturing, and relation of petroglyphs to other settlements, features, and material culture. Moreover, this research seeks to build the only comprehensive dataset on petroglyphs in southern Costa Rica, using GIS, 3D scanning, and drone technologies to record their geospatial and contextual information, including surface finds and other structures, or related sites. This will enable their preservation and continued study without requiring physical access and will be particularly insightful concerning their manufacturing, use, and erosion rates. While interpreting petroglyph iconographies is unlikely, this research seeks to gain insights into recurring motifs and possible regional patterns to aid future interpretative studies. It also strives to understand potential relationships between different kinds of stoneworking and the presence or absence of certain iconographies. This project will culminate in two open-access databases, comprising geospatial information of petroglyphs, settlements, and sites, as well as respective 3D models. This ensures digital petroglyph preservation and enables global accessibility, fostering interdisciplinary collaboration. Integrating geospatial analyses with laser scanning and modelling approaches, this research will provide essential tools for archaeologists and open new avenues for understanding the archaeology and heritage of the pre-Columbian Central Americas.