This paper focuses on the urban context and spatial manifestations of the construction of shared heritage sites resulting from cross-border interactions in Polish-German border towns. A comparison of the three border towns of Frankfurt(Oder)/Słubice, Guben/Gubin and Görlitz/Zgorzelec offers insights into the relationship between the creation of transnational urban places and the contrasting spatial circumstances in the urban environments of the border towns. The greater permeability of the border in the Schengen period from 2007 has intensified cross-border activity, and actors from both sides of the river have cooperated to create new shared places, most prominent among these are heritage sites. These new transnational heritage sites emphasise different aspects of the past, including valorising ‘neutral’ heritage, rediscovering sites of trauma and victimhood, or reinventing existing sites. While divisions persist, rooted as much in the burden of the past as current socio-economic asymmetries, some evidence is coming to light of the forging of shared heritage sites linked to narratives of reconciliation and mutual recognition. The creation of shared heritage is a fragile process which depends on contingent urban conditions. This paper draws attention to the need for heritage sites to evolve gradually and with significant participation from civil activists if they are to gain local transnational significance. Moreover, heritage sites only have transformative potential when they become integrated in the urban environment as active settings for everyday life which transcend commemorative or tourist purposes alone.