Montagnes Noires
The Montagnes Noires (French: 'the black mountains'), also known as the Montagne Noire (French: 'the black mountain') and in Breton as Menez Du are an east-west oriented range of hills in Brittany centred on the town of Gourin. They culminate in the peak of Roc de Toullaeron (Breton: Roc'h Toull-al-Laeron) which attains a height of either 318m or 326m. Other significant peaks include Ar Menez (304m) and Montagne Noir (307m) (or, in Breton: Menez Du). They are composed from a range of Precambrian, Ordovician, Silurian and Devonian rocks forming a part of the Variscan orogen and include sandstones, quartzites and slates.
The hills form a part of the border between the départements of Finistère and Morbihan and just extend into Côtes-du-Nord.
Coordinates: 48°09′N 3°40′W / 48.150°N 3.667°W
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