The Achelous (, Akhelôios), also Acheloos, is a river in western Greece. It is long. It formed the boundary between Acarnania and Aetolia of antiquity. It empties into the Ionian Sea. In ancient times its spirit was venerated as the river god Achelous. Herodotus, taking notice of the shoreline-transforming power of the Acheloos River, even compared it to the Nile in this respect: 'There are other rivers as well which, though not as large as the Nile, have had substantial results. In particular (although I could name others), there is the Achelous, which flows through Acarnania into the sea and has already turned half the Echinades islands into mainland.' (2.10, trans. Waterfield) It is said to have been called more anciently Thoas, Axenus and Thestius. Course The river Achelous begins at about elevation on the eastern slope of Lakmos mountain in the Pindus range, near the village Anthousa in the westernmost part of the Trikala regional unit. One of its first tributaries is the Aspropotamos, meaning the white river. The river flows generally southwards, and forms part of the boundary between the regional units of Arta and Trikala, which is also the boundary between Epirus and Thessaly. Further downstream, it forms the boundary of Arta and Karditsa, and further of Aetolia-Acarnania and Evrytania. The river runs into the Kremasta reservoir, which is also fed by the rivers Agrafiotis and Megdovas. On exiting the Kremasta reservoir, the river flows southwest into Aetolia-Acarnania, feeding the Kastraki reservoir, west of the Panaitoliko range. downstream from this lake, it flows into the Stratos reservoir. Further downstream, it runs through the lowlands west of Agrinio. It finally empties into the Ionian Sea, west of Missolonghi. Settlements In order from upstream to downstream: Katafyto Gardiki Mesochora Koryfi Myrofyllo Petroto Grimpiana Mesopyrgos Neo Argyri Tripotamo Kastraki Stratos Palaiomanina Gouria Neochori Dams There are five dams on the river. From upstream to downstream there is the Mesochora Dam which was completed in 2001 but has not impounded its reservoir. Below that is the Sykia Dam which is partly constructed. Further down is the Kremasta (1965), Kastraki (1969) and Stratos Dams (1989). Acheloos River in mythology History In antiquity, the Achelous was the largest and most celebrated river in Greece, rising in Mount Pindus, and after flowing through the mountainous country of the Dolopians and Agraeans, entered the plain of Acarnania and Aetolia near Stratus, and discharged itself into