Citizen participation helps to involve local knowledge in the urban planning process and prevent unsatisfied citizens. This research investigates how design can give concrete substance to affording citizen participation as the exploration of needs and wishes with citizens, rather than extracting information from them. We showcase a design project in which we joined with the municipality of Eindhoven, the Netherlands, in facilitating such participation in the process of redesigning the Town Hall Square of Eindhoven. In this project, we designed and tested an interactive, situated installation with which citizens could explore their view on the future of the square through bodily movements. We present narratives and observations from this test and contribute by highlighting three design qualities of the installation that facilitated exploration: continuous reshaping, unfamiliarity and ambiguity, and situatedness. With this research we hope to inspire designers to continue investigating explorative modes of citizen participation.