It is a true architectural masterpiece, by some unknown but great architect. It lies in the center of the city, on the western side of the wall, adjacent to the Roman agora. It was used for lectures, literary and musical contests and theatrical performances during the Nea Aktia religious games honouring Apollo. It was built during the reign of Augustus (early 1st century AD) and frequently remodelled and repaired in the late 2nd - early 3rd centuries AD. The Odeon consisted of the cavea, the orchestra and the scene. The cavea contained 19 rows of seats and was divided into two sections by a small horizontal central corridor. On the tenth row of the seats, there were small openings in favour of acoustics. Three semicircular porticos, of different heights, support the cavea and ensure its sloping tendency. The semicircular orchestra was adorned with multicoloured marble works, parts of which are still preserved. Between the scene proper and the proscenium there is a deep and narrow corridor. This is "the flute of the setting", which served to raise the curtain at every theatrical performance.

It is an impressive building erected in the early 1st century AD, together with other public buildings in the city. It operated mainly during the religious celebration of the Nea Aktia, in honor of Apollo. Lists of winners in the Nea Aktia contests found in the temple of Apollo inform of competing poets, sophists, comedians, heralds, trumpeters, guitarists, announcers, pipers and mimes. The theater was built on the slope of a hill and in an effort to increase protection from earthquakes, a high buttressed wall was built around the cavea. A wide corridor called diazoma divided the cavea into two sections, the theater and the epitheatro. At the corridor’s edges were two large vaulted entrances. The cave supported a peripheral portico probably sheltering spectators in case of a sudden storm. Both the orchestra and the cavea were shaped as a regular semicircle. There was a high, probably two-storey, scene (characteristic of the Roman architecture) with three arched entrances at the facade.

The most famous nekromanteio (oracle of the dead) of the ancient Greek world lies near the shores of the Acherousian Lake, where Acheron and Kokkytos, the rivers of Hades, meet. Ancient literary sources describe the Acherousian Lake as the place where the dead began there descent to Hades, and associated Ephyra, the city located further north, with the ancient cult of the god of death. The nekromanteion attracted people wishing to meet the souls of the dead, as these were able to foresee the future after having left their body. Homer provides the earliest reference to the nekromanteion in his Odyssey, when Circe advises Ulysses to meet Teiresias, the blind seer, in the Underworld, in order to get an oracle for his return home. The earliest use of the hill where the nekromanteion is preserved dates saved back to the Mycenaean period (14th-13th century BC). The remains date back to the Hellenistic period. The sanctuary operated in this form continuously for approximately two centuries. It was burnt down and ceased to function after the Roman conquest of Macedonia in 167 BC. It was occupied again in the 1st century BC when Roman settlers arrived in the plain of Acheron.

Built on a spacious plateau, on the southern slopes of Zaloggo mountain range, in a naturally fortified and strategic position, it is the balcony of the prefecture of Preveza. It offers a unique view over the Ionian Sea, Amvrakikos Gulf, the island of Lefkada and the Acarnanian coast. Cassope was built in 340 BC but it flourished after the late 3rd century BC. At that time, its population ranged between 8,000 to 10,000 inhabitants. It is a characteristic example of an integrated urban center of the Epirote tribes. The Hippodameios planning system was used during its construction. It had an integrated sewerage system which channeled the water waste to the separating sewer of the homes and from then to a larger network of drains which disposed it outside the wall. It acquired economic power with the trade, livestock and the products of the fertile plain of Acheron river and had its own mint. The city had a civilian agora, a prytaneum, two theaters, a hostel, and temples of worship of Aphrodite and Zeus the Savior. Its prosperity came to an end in 167 BC when it was destroyed by the Romans and was finally abandoned with the compulsory cohabitation of its inhabitants in Nicopolis.

The origins of the sanctuary of Dodona, which is known for its nationwide radiation, date back to the Bronze Age (2600-1200 BC). Originally, it was outdoors and it was there that the Great Goddess, goddess of fertility, was worshiped; later, it was replaced by the worship of Dodona Zeus (Zeus Naios) and his wife Dioni. The priests uttered the oracles by listening to the rustling of the leaves or the sound of the tripods around the sacred oak of Zeus (fagus). The Naia, famous Panhellenic games, were held in honour of Zeus. The first temple, the “Sacred House”, started being built in the 4th century BC. However, the Sanctuary was fully renovated in the 3rd century BC, during the reign of King Pyrrhus. At around the Prytaneum, the Bouleuterion and the Theater, which is one of the biggest ancient theaters of Greece (approximately 17,000 seats), were built. Homer, and other ancient Greek writers, mentions the oracle of Dodona as the oldest in the Greek world.