The border runs along the center of the lake, but makes landfall before reaching the mouth of the Rhone, at St-Gingolph. From here, the border runs south and south-east into the High Alps, forming the western border of the Valais. It passes Les Cornettes de Bise (2431 m), Dent de Barme (2759 m), Petit Ruan (2846 m), Pointe des Rosses (2965 m), Pointe de la Fenive (2838 m), and Le Cheval Blanc (2830 m), placing Lac du Vieux Émosson in Switzerland.