This paper studies the role of cross-border interactions and public spaces in the local mediation of national conflicts in three Polish-German border towns. It draws on Luc Boltanski’s pragmatic sociology in order to address questions raised in the recent literature on urban conflict and borders. Our analysis traces transformations under Schengen in relation to Boltanski’s concepts of uncertainty, justification and tests. We investigate ordinary inhabitants’ everyday experiences of cross-border relations through different types of spatial practices and place-making strategies in the context of a shifting border. Recent transformations have started to challenge a longstanding situation of ‘arrested conflict’ rooted in blocked local networks, disconnected from supranational discourses of cooperation.