The ruined village of Faudon

What are these piles of stones lined up in the grass below the Croix St-Philippe? In a perfect position on a small, sunny plateau, there are walls, entrances, streets. This is the former village of Faudon, and was once home to the inhabitants of Ancelle. 
Archaeological excavations have dated occupation of the site back to around 400 to 600BC, so the village appears to be older than Gap itself! The strategic position of this promontory made it perfect for a succession of observation structures down the centuries, including a Roman signal tower which was fortified in the eleventh century. In the Middle Ages, the site was occupied by more than 400 people but in 1210 a fire destroyed the Tour Saint-Félix together with the church and homes, leading to the abandonment of the village. The inhabitants settled in the hamlet of Château d'Ancelle.