Despite a variegated body of academic work on nation-building and rail infrastructures, attention to the relationship between nation-building and wider processes of economic and political restructuring and an explicit and theoretically robust consideration of space have been largely missing. This paper seeks to address both limitations by advancing a spatially sensitive conceptualization of how rail infrastructures may be used as a tool for nation-building in contemporary capitalist societies. Particularly, I draw on Jessop's strategic-relational approach to the state and on theoretical contributions on the spatiality of social relations to propose the synthetic notion of ‘spatial hegemonic vision’ to explain the legitimacy and substantive coherence of state action, argue for the inherent spatiality of nation-building projects, and facilitate a theoretically robust and nuanced understanding of such spatiality. I further distinguish between political economic and cultural dimensions in nation-building and discuss the materialization and imagining of specific configurations of territories, places, scales and networks involved in spatial hegemonic visions. This conceptualization is then applied to the development of a high-speed rail line in the Spanish region of the Basque Country. This line has been mobilized to advance two competing yet partially compatible spatial hegemonic visions, whilst becoming itself a site where they came into conflict. The paper concludes by examining the validity of the proposed conceptualization and discussing its applicability to other contemporary cases of nation-building through transport infrastructures.