Causse de Sauveterre
The northernmost of the causses is a gentle, hilly plateau dotted with a few isolated farms and traversed by hiking trails. Every possible patch of fertile earth is cultivated, creating irregular, intricately patterned wheat fields.
Causse Méjean, the highest of the causses, is also the most barren and isolated. Defined to the north by the Gorges du Tarn and to the south by the Gorges de la Jonte, it looms over Florac, on its eastern flank. It’s a land of poor pasture enriched by fertile depressions, where streams gurgle down into the limestone through sinkholes, funnels and fissures.
This combination of water and limestone has created some spectacular underground scenery, particularly at Aven Armand.
Rising immediately east of Millau, the Black Causse is best known for the Chaos de Montpellier-le-Vieux.
Causse du Larzac
The Causse du Larzac is the largest of the four causses. An endless sweep of distant horizons and rocky steppes broken up by medieval villages, it’s known as the ‘French Desert’.
You’ll stumble across venerable fortified villages such as Ste-Eulalie de Cernon, long the capital of the Larzac region, and La Cavalerie. Both were built by the Knights Templar, a religious military order that distinguished itself during the Crusades.
Gorges de la Jonte
The spectacular 20km-long Gorges de la Jonte cleave east–west from Meyrueis to Le Rozier, dividing Causse Noir from Causse Méjean. They're much more lightly trafficked – though busy enough in summer – than the more famous Gorges du Tarn.