Aktio Fortress is located 12 km west of Vonitsa and 2.5 km north of Aktio airport, on the Akarnanian coast opposite Preveza. It was built by Ali Pasha of Ioannina in the period 1805-1812 (probably in 1809), in order to control the coast of Akarnania and the entrance of Amvrakikos Gulf. Therefore, the area is related to the famous naval battle of Aktio on 2nd September 31 BC, in which Octavian’s forces defeated those of Mark Antony and Queen Cleopatra of Egypt. For the construction of the fortress, was used ancient building material, brought from the area around Aktio.
It is a small, triangular planted fortress of quite unusual design, which can be compared to the castle in Porto Palermo (near Himara in southern Albania). It consists of a tall perimeter wall, with peridrome and parapet that carries three voluminous polygonal bastions at its apexes. This wall surrounds an internal triangular courtyard. The largest northern horseshoe bastion faces to the Amvrakikos and the others two, simple rhomboids to the city of Preveza and Ionian Sea. The height of the walls reaches 6 m. Its total perimeter is estimated at 175 m., while its unique entrance gate is on the north side, where after an elongate interior corridor, leads to the paved triangular yard. On the inside, around the triangular yard, there is a series of small quadrilateral dome-covered spaces, open-hearted on the inner side of the wall. A ramp leads to the peridrome of the wall, which is protected by a parapet (low enclosure wall), pierced by a large number of loopholes for firearms, while in the bastions there are places for cannons.