Lavinium was a port city of Latium, 6 km (3.7 mi) to the south of Rome, midway between the Tiber river at Ostia and Antium. 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 Antium, was evidently the mouth of the Numicus river.
The location of Lavinium has never been lost to historians nor does there appear to have been any significant break in its habitation. Today's settlement remains a walled village of medieval design, Pratica di Mare, in the comune of Pomezia. The latter is a city constructed in 1939 and settled according to a plan of Benito Mussolini, whose engineers completed the millennia-long task of draining and filling the marsh, now the Pontine fields. A brief strip of field separates the large and flourishing city from the village. One Roman gate allows entry into the narrow streets of the village past the Castello Borghese, originally a fortification, purchased along with the village in 1617 by Marcantonio Borghese. The castle and the village were periodically renovated. All that remains of the river that once partly surrounded the village is a small stream, the Fosso di Pratica.
Pratica di Mare is about 6 km (3.7 mi) from the Tyrrhenian Sea near the top of a slope descending to an alluvial shelf on which the Pratica di Mare Air Force Base has been placed. It has the historical distinction of being the airfield from which Otto Skorzeny flew Mussolini to safety in Germany after his rescue from imprisonment in a mountain villa. Today the base is both a secure airport for the protection of distinguished visitors to the Rome region and a home for air shows of advanced aircraft. The Fosso di Pratica was re-routed around the end of a runway; however, today's small brook is in no way compatible with the concept of a port. The sea may well have formerly extended up to the base of the hill, as sites further north, such as Ostia, appear to have retreated one or two miles inland. Ancient Roman seaside villas are no longer on the beach.