Parco archeologico di Ostia antica (Scavi di Ostia)

The park's own account takes the town's name from ostium, mouth, and records the tradition that Ancus Marcius founded it in 620 BC to work the salt pans, while the remains identified on the ground begin with the tufa-block castrum of the second half of the fourth century BC. Walls of about the middle of the first century BC enclosed roughly sixty-nine hectares behind three gates; population estimates for the second century AD run to around fifty thousand; commerce moved to Portus from the middle of the third century AD and literary sources describe the town abandoned by the middle of the sixth. The Tiber ran along the north side of the town until the flood of 1557, and the coastline is now about four kilometres away. The park is an autonomous institute of the Ministero della cultura created on 23 January 2016, directed by Alessandro D'Alessio since 30 October 2020, and it also administers sites in the Comune di Fiumicino. A birdwatching hide, Aves ostienses, stands on via della Foce inside the excavation under a three-year agreement with LIPU, which manages the hide and the neighbouring Casetta del Custode n. 4 and runs bird censuses on the site.