Louros river springs from Tomaros mountain in the prefecture of Ioannina, and empties into the Amvracian Gulf. Its importance for the surrounding area becomes obvious from the fact that in 31 BC the Roman emperor Octavianus Augustus ordered the construction of a huge aqueduct, measuring more than 50 kilometers long, in order to supply the newly-founded city of Nikopolis with water from Louros river.

Nowadays, the ruins of the aqueduct lie in the area of Agios Georgios of Philippiada, at a distance of 25 kilometers from Arta.