Mountains dominate the north, northeast, west and southeast, especially the
Acarnanian Mountains. The longest and main river is the
Acheloos, which ends as a delta in wetlands to the southwest on a rich fertile valley. The second longest is
Evinos; others include the
Ermitsa, the
Inachos, and the
Mornos (on the border with Phocis). The regional unit excludes the islands lying to its west, since they belong to the
Kefalonia and
Ithaca regional units. There is one reservoir and a lake in its central part. The many mountains of the area span the
Panaitoliko toward the northeast and the
Acarnanian Mountains, the
Valtos and the
Makrynoros mountains in the north, the
Nafpaktia Mountains in the southeast, the
Arakynthos and
Kravara in the south. Lakes include the
Amvrakia, the
Lysimachia,
Ozeros, and
Trichonida, and artificial lakes and reservoirs include
Kastraki,
Kremasta, the largest lake in Greece since its creation in 1970, and
Stratos. Two lagoons are found in the southern part of the regional unit: the
Messolongi and the
Aitoliko. The lowest altitude in Greece is found in west Aetolia-Acarnania at about -10 meters from the sea level.
Climate Its climate ranges from hot and humid summers, with temperatures often surpassing 40 °C, to mild and short winters in the low-lying areas, with cool winters dominating in the mountain areas. At the highest elevations, summers are cool, and snow and cold weather dominate the winter months in the Panaitoliko. ==History==