The archaeological site known as the “Villa degli Antonini” lies in the SE sector of the Alban Hills within the modern comune of Genzano di Roma and some 1.5 km north of the ancient urban center of Lanuvium (Lanuvio) (fig. 1). It is c.400 m south of the Via Appia between that road's 18th and 19th milestones (it seems to have been connected to the Via Appia by a side road traceable in historic aerial photographs and of which a section is still preserved) and c.1 km south of the rim of the volcanic lake of Nemi, from which the ground slopes gently down towards the coastal plain of Latium. To the west and east are two scoria cones, Monte Due Torri and Montecagnoletto, the latter of which was once separated from our site by a N-S valley c.100 m in width.