Why?

Up above the vineyard, on the ridge known as La Coste de St Andrieu there is a wall. This two metre high dry stone wall runs for hundreds of metres and separates..... Well, I have no idea what it's for. Why would anyone build a huge straight wall along the top of a remote ridge, then build gaps onto it like this one?

Any ideas?

This view is towards the north and the village of Vailhan. When you turn to look back south there is the Mediterranean on the horizon. With long low flatlands covered in vines it could not be more contrasted with the northerly vignette. I love both views equally.