Lavinium was a port city of
Latium, to the south of Rome, at a median distance between the
Tiber river at
Ostia and
Anzio. The coastline then, as now, was a long strip of beach. Lavinium was on a hill at the southernmost edge of the
Silva Laurentina, a dense laurel forest, and the northernmost edge of the
Pontine Marshes, a vast malarial tract of wetlands. The basis for the port, the only one between Ostia and Anzio, was evidently the mouth of the
Numicus river.