Tracing the informal fringe: A large-scale study of 20th century 'wild' settlements in Vienna, Austria

Informal urbanization in the global North is an emerging field of research. Likewise, the need to expand existing morphological analysis into informal settlements is well established but lacks material. As our long-term study is able to show, Vienna was one of the European 'capitals' of informal urbanization in the 20th century. Drawing on both historical and present-day geodata and surveys, we trace the emergence and transformation of 'wild' set-tlements over the course of a century. City-wide GIS-reconstructions help us to localize and quantify Vienna's informal fringe. We discuss situational and site factors, the spatial patterns of clearance and legalization. Our research documents the remarkable scale and persistence of Vienna's 'wild' settlements. By the mid -1900s, the self-made "city of settlers and gardeners" had transformed more than 43 km2 of peri-urban terrain. Formalization and infrastructural retrofitting were a piecemeal process that lasted until the early 2000s, in some cases even until the present. It resulted in a patchwork of both legal status and urban tissues. The informal 'facts on the ground' not only came to structure and shape the residential suburbs of today's agglomeration, but also fed back on the planning instruments and the authorities that tried to enforce them.Informal urbanization in Vienna, as is often the case in the Global South nowadays, was a mode of production of space driven by desires for a better life, for autonomous nutrition and affordable housing. Tracing Vienna's 'wild' fringe, we conclude, helps to further demythologize the notion of "Northern formality" and contributes to a small, but growing number of long-term studies on informal (sub)urbanization. Moreover, our study shows that there are ways to reconstruct the settlement patterns of the urban poor even for the pre-google-earth era, pro-vided there is the necessary source material and technical capabilities. Thus, it contributes to the methodological array in urban studies and the study of urban form in general.