How can we observe and investigate the spaces built and transformed by large infrastructural projects? What actors, strategies, and scales should be kept under observation? What are the relationships between the so-called ‘global infrastructure turn’ and urbanisation processes? By asking these questions the article introduces the section, whose focus is on the spatial transformations associated with recent infrastructural development along the so-called ‘Adriatic Corridor’, starting with the ports of Trieste and Piraeus. The article discusses the need to overcome a purely technical view of infrastructures and their processes, in order to recognise their current ‘leap in scale’, and to see these interventions from the ground as part of the new forms of contemporary urban phenomena.