The Fossa Traiana (Channel of Trajan) describes a canal of ca. 45 m width connected with the artificial harbors at Portus. Despite the name, its origins may lie in the Claudian harbor works. The cutting of the channel created an artificial island between Ostia and Portus, the so-called Isola Sacra.
Description via Pleiades. Coordinates and heritage data from the Atika atlas.
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