The Threshold City The urban scenery is regularly affected by calamities, disasters. Today we have a good knowledge of those disasters by the point of view of sociology, psychology and emergency management. Nonetheless, in the urban studies, there isn’t any concept useful to define the situation of a city after a disaster. In the period after an emergency we can observe a particular urban event, even though declined in different situations, and recognize a precise phenomenology of it? The expression "threshold city", kept from Walter Benjamin’s Paris, die Hauptstadt des 19. Jahrhunderts, try to be a concept-bridge, able at the same time to define this situation, and to open a debate to develop the specificity of it, to give to planners and analysts the instruments and a survey useful in those cases.
Keywords: Threshold city, disaster, emergency, reconstruction, urban planning, psychology of emergency.