A new tunnel - the first and so far only undersea tunnel in Greece - which runs between Preveza and Aktio, connects the town to Thesprotia and Lefkada and western Aetolia in Aitoloakarnania. Preveza lies near the western part of the Ambracian Gulf. The ruins of the ancient city Nicopolis lie 5 km north of the city. Its population per the 2001 census is 17,724.
Preveza was not populated during classical antiquity but there is evidence that it served as a sea port in the days of King Pyrrhus of Epirus. On September 2, 31 BC, the naval battle of Actium took place just off its coast, between the fleet of Octavian and the combined fleets of Mark Antony and Cleopatra VII. In commemoration of his victory, Octavian built Nicopolis ("Victory City") nearby.