Work

Generative inference model reveals political and economic motivations for road construction in past societies

Year: 2026

Type: article

Abstract: The construction of roads in past societies reflects a trade-off between a preference for straightness and the influence of slope gradient. This trade-off is, however, also conditioned by other factors, principally the political and economic motivations of a past society. Our understanding of this trade-off and its relationship to these motivations is poor, hindered by qualitative studies that fail to explain variability in road construction, and non-comparative quantitative approaches. Here, we introduce a hierarchical, generative inference model that simulates roads using explicit decision rules to estimate the influence of slope gradient on 62 well-evidenced Roman roads in modern-day Wales. Our results reveal substantial variability, with Roman roads not conforming to a single unifying straightness-gradient trade-off. We relate this trade-off to political and economic motivations to provide a unified, comparative framework for inferring motivations for road construction, both within the Roman Empire and across past societies more broadly.

Source: Humanities and Social Sciences Communications

DOI: 10.1057/s41599-026-09179-4

Authors: Joseph Lewis, Enrico R. Crema

Institution: University of Cambridge

Language: English

Topic: Archaeological Research and Protection

Subfield: Space and Planetary Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDGs: Sustainable cities and communities, Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $1,890