Gastouni (Greek: Γαστούνη) is a town an a municipality in northern Elis, Greece. Distance is 10 km south of Lechaina, 16 km from Kyllini Baths, 28 km from Pyrgos, 12 km NW of Amalias and 70 km SW of Patras. Its population is 7,524 and is the prefectures' third largest community which includes towns and cities as well as the metropolitan area of Pyrgos. It sits west of the Peneus valley and south of the Pineios River. The neighboring communities are Vartholomio to the west, Kavasila in the north, Agia Mavra in the NE, Koroivos in the east, Savalia in the SE and Palaiochori in the south. GR-9/E55 since the late-1980s bypasses Gastouni. Most of the residential houses lie east of the old GR-9. The town has about 600 m to 800 m of one-way streets. Elevation is about 4 to 5 m above sea level. A Byzantine church of the Panagia Katholiki is two-columned and built in the 12th century.