Ostia, once the great port of the ancient Rome, is now the tenth municipality of the capital. There is no historical or functional continuity between the old and the new city. The first is now only an archaeological site; the second, which developed as a seaside district, has become a satellite of the capital, which tends to use it to divert attention from its own critical issues. However, liminality is not an inescapable fate for Ostia. The reacquired importance of the Mediterranean dialogue could make it a strong point for the capital and the country.
Keywords: Liminality, Ostia, Rome, sea, periphery, archaeological sites