Adria (river)

Adria (Greek: Ἀδρίας) was a former channel of the Po delta passing by Adria that ceased in the 1st century BC.

This river was mentioned by Hecataeus, by Theopompus and by Ptolemy.

Hecataeus asserts that the Adriatic sea and the town of Adria were named after this river.

Between the 12th and the 9th century BC the mainstream of the Po followed this channel; its course followed more or less today's system of the Fissero-Tartaro-Canalbianco canals and flowed into the Adriatic Sea by the site of Adria. At that time the coastline was far more upriver than nowadays. The first hamlets of Adria were settled by the Veneti; also the settlement of Frattesina, near modern Fratta Polesine, was active by this river during these centuries.

During the 9th or 8th century BC the mainstream of the Po river changed, due to the so-called "breach at Sermide", and followed a channel more to the south, the Spina river. The Etruscans dug canals in order to drain the "Adrian swamps" (i.e. the swamps that surrounded Adria); the Tartaro river was diverted north-east into the Philistina canal and other canals (the fossiones) were dug parallel to the coastline in order to allow inland navigation instead of coastwise. The town of Adria and its port on the Adria river flourished in the 6th century BC; new settlements were founded on dry land, inland from the sea, up the Adria and lesser streams.

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