This volume is the first in a series of works detailing the archaeological investigations of the ager Rusellanus, in coastal southern Etruria, undertaken by the Alberese Archaeological Project. It focuses on the Roman temple and sanctuary dedicated to Diana Umbronensis, located at Scoglietto (Alberese – GR) on the ancient Tyrrhenian coast. In so doing it adds to the study of trade and settlement networks in ancient Italy, and provides new data on the character of Roman and late antique Etruria. The book discusses the changing aspect and character of the sanctuary over approximately eight centuries – from its foundation in the mid-2nd century BC and substantial refurbishment in the Antonine period, to its destruction in the 4th century AD and the varied use and reuse of the site through the following two centuries. It includes archaeological, historical and landscape studies, as well as detailed architectural and material culture studies for a composite interpretation of the site and its history.