Empty, abandoned or covered with vegetation – such areas were inherent to the medieval urban space, yet remain overlooked in research. Here, we describe three major types of ‘empty’ space of various origins and functions in Central European towns and suggest how these types can be investigated and interpreted through an interdisciplinary approach combining archaeological, written, pictorial and cartographical sources. We propose a simple interdisciplinary protocol to trace empty spaces in the urban context. This study will help to change our perception of medieval urban space into one that is more dynamic and heterogeneous than commonly believed.