Archaeological features without macro-finds (i.e. finds visible with the naked eye) represent a common phenomenon that poses considerable methodological problems in interpretation. To tackle these problems, we present an approach based on integrating micro-archaeological methods and macro-observations to help elucidate ‘invisible’ activities or at least to exclude certain others. Specifically, we combine micromorphological and micro-debris analyses with the scarce macro-finds and their fragmentation degree to clarify whether the lack of evidence for certain activities really reflects their absence or merely bad preservation conditions. This study focuses on a Late Iron Age ‘empty’ enclosure excavated in the settlement site of Haselbach, Lower Austria. ‘Empty’ square enclosures of the La Tène Culture have been controversially interpreted as either sanctuaries, domestic buildings or burial enclosures, although these interpretations were rarely supported by any material evidence. Using a multi-proxy approach enables us to reconstruct the formation processes of the Haselbach feature as well as to rule out a range of activities, although a clear definition of its primary function was not reached. Based on our case study, we propose a research protocol that can be applied to research on similar ‘empty’ features in order to better validate their functional interpretations.