Heike KRAUSE, Stadtarchaeologie Wien, Austria

Intensive research into the fortifications of Vienna was prompted by several excavations carried out by the Stadtarchäologie Wien in recent years in the city centre. It led to an interdisciplinary project, which has resulted in numerous publications. Written and pictorial sources relating to the medieval defences and the early modern fortifications were attained and analysed critically, while excavation results were brought together. Not only the historic phases of the fortifications up to and including their demolition, but also the architects and engineers responsible were revealed in this way. With the help of geo-referenced historical plans and archaeological data, the course of the medieval town wall and the extent of the later fortifications were reconstructed and the former structures located in the modern urban area. The Urban Fortifications GIS developed on this basis enables the accurate definition of areas of potential concern, meaning that precise predictions about probable existing remains can be made in advance of construction projects.