The socio-economic impacts of high-speed rail: a cross-national comparative review

High-speed rail (HSR) has become a transformative mode of transportation, generating significant socio-economic impacts across different national contexts. This paper presents a comprehensive cross-national review of HSR’s effects, analyzing 491 empirical studies published between 2008 and 2023. We systematically compare outcomes across three distinct governance models: China's centralized, state-led approach; Japan's market-integrated system; and Europe's decentralized, cohesion-focused framework. Our analysis is structured around six key socio-economic domains: population distribution, economic development, social welfare, innovation, environmental outcomes, and integration with other transport modes. Findings show that while HSR enhances connectivity, fosters innovation, and stimulates economic growth, it can also deepen spatial inequalities – particularly when not supported by inclusive regional policies. In China, HSR has accelerated agglomeration, reinforcing the dominance of megacities and facilitating industrial upgrading, yet often at the expense of peripheral regions, thereby deepening spatial inequalities. Conversely, the European Union has strategically utilized HSR within its cohesion policies to foster more balanced, polycentric developmen. Japan’s mature Shinkansen network demonstrates how market-driven systems can enhance efficiency but also tend to reinforce existing urban hierarchies, particularly problematic in the context of an aging and stagnating population. We emphasise that HSR is not an inherently equitable technology. Its outcomes are mediated by underlying institutional structures, demographic conditions, and specific policy objectives. The paper concludes with policy recommendations designed to promote equitable and sustainable HSR development. It identifies key research gaps in areas such as multi-scalar integration, long-term social impacts, and intermodal coordination.