The rugged field and group of trees between housing estates or next to the railroad tracks, the left-over space of deserted industrial areas, the vacant demolition site of a central city block – they could all be termed ‘urban voids’. However, they are often anything but voids, in a literal sense, as they are not empty, or deserted. Yet they are ‘urban voids’, lacking an evident function, or a definition according to a plan. It is a category of urban space constructed as a nothingness, even though the very same space is often used for a variety of purposes. The aim of this thesis is to show how the urban void becomes as the constitutive outside of the City. It investigates the difference made between well-defined urban spaces (known by name...