The internet says that it is Gallo-Roman, an altar bench with a shell that resembles the fossilized shells that are contained in the stone mined in the quarries in the area. Apparently, one can also see the carving of a bull's head somewhere in the structure. Possibly a site of worship for a water deity. Roman quarry and drainage galleries nearby.Has anyone seen this stone carving of a scalloped shell between Paradou and Fontvielle? Possibly it is an ancient marker for early pilgrims of the Chemin d Arles? This was pointed out to me recently by friends who live nearby.