sentences:  The town is located south of Lake Trichonida, the largest natural lake of Greece.It is 7 km east of Papadates, 10 km northwest of Kato Makrinou and 15 km southeast of Agrinio.Gavalou may be built at or near the site of the ancient Aetolian town Trichonium, from which the Lake Trichonida derived its name.