This little village that nestles against the hills and stretches out along the Rhône is a key site of prehistoric and medieval settlement. It is named after "Soïo", a local divinity worshipped in the 7C BC. The protected site, which extends over approximately 30ha, is being progressively excavated. It has so far yielded valuable information about the different periods of occupation of Soyons to have succeeded each other over around 150 000 years. The caves, too, were occupied very early on by man. The Musée Archéologique also pays homage to the village's long history.