This article reports the findings of the fieldwork exploring the cisterns at the Bisti promontory of Hermione, executed as part of a collaboration between the Ephorate of Antiquities of the Argolid and the Swedish Institute at Athens. In order to better understand the function of the cisterns within the water supply system, the article begins by presenting an overview of existing water resources in the area, primarily the naturally occurring sources and the city’s 2nd-century AD Roman aqueduct. Following this the study describes the remains of the 14 potential cisterns on the Bisti. Based on the empirical material the similarities and contrasts between these are explored, as well as what they can tell us about the history and life in ancient Hermione. In particular, the article suggests that the presence of the cisterns contributes to our understanding of the urban fabric of the city, and reveals important information about when the city was moved from the Bisti to the nearby Pron Hill.