Magnetometry surveys of two areas of ancient Praeneste were completed during a five-day season in early November 2003. The work successfully revealed and accurately mapped the presence of building structures at both sites. Most of the highlighted anomalies display morphological characteristics associated with planned buildings and structures. More specifically, at Villa d’Adriano several prominent features most probably correspond to the villa complex or perhaps even indicate the vestiges of a peristyle garden from the Roman period. Similarly at Ville Fiorentini results again suggest a series of arranged rooms perhaps laid out in conjunction to road or pathways. Kilns may furthermore be a feature of this site.