The geographic space of the old Trinational Agglomeration Basel is a complex area where municipalities (and urban systems) belonging to three different countries meet, and part of a paradigmatic scenario where former and recent cross-border cooperation structures and practices are opening opportunities for joint development. The purpose of this paper is to analyse how organisation and spatial relations are being transformed in this context and if there exist barriers, focusing on Weil am Rhein (Germany), Basel (Switzerland) and Saint-Louis and Huningue (France), which converge in the heart of the Agglomeration.
The paper is structured in two parts. The first one is a theoretical exploration of the evolution and extent of cross-border cooperation structures and practices affecting the area. The second one focuses on urban transformation and intertwining resulting from this environment, exploring it through analytical work and cartographies for the 1985–2010 period. In this study, three categories are considered: transport networks, morphology and land use.
Results suggest that cooperation structures are bringing opportunities for the interweaving of neighbouring border urban spaces. However, significant limitations due to regulatory and spatial inheritances and economic constraints, among others, persist. The analysed space continued evidencing barriers and over-simplified areas at the end of the period studied.
The research offers a not-so-frequent, but necessary, perspective of border urban systems as complex scenarios: not only nodes of interaction but also inhabited spaces. It provides insights into border urban development and original cross-border cartography, giving clues on planning in singular environments.
