It is the various climates, soils and grape varieties that make Côtes du Rhône wines so characteristic, but more than geographical unity, perhaps, it is the desire and labour of the winegrowers that have given the wines their real personality, and enabled the attribution of an AOC.
The climate is Mediterranean, its most striking feature being the mistral, the strong wind born of the difference in atmospheric pressure between the north and the south and that is so beneficial to the vines. The region's climate is characterised by its seasonality, with heavy rains, high temperatures and exceptional amounts of sunshine.
The soil is the result of the combination of the vegetation and the climate over thousands of years. The Rhone has left a powerful mark on the whole of the sedimentary basin, carving out the relief and bringing alluvia that have created, from Vienne down to Avignon and the Cévennes, against the foothills of the Alps, a rich variety of soils.
The grape varieties come originally from three different vine-growing regions. The Cinsault, Clairette and Bourboulenc are varieties that were first developed in the Mediterranean regions of France. The Grenache, Carignan and Mourvèdre came from provinces in Spain, brought in by travellers around two centuries ago. The Syrah, Roussanne, Marsanne and Viognier are thought likely to have come from wild vines that grow in the forests of Dauphiné.
From Vienne to Valence, the vineyards cover the right bank of the river through the départements of Rhône, Loire and Ardèche. On the left bank, they spread out over the steep slopes around Tain-l'Hermitage. This whole area is characterised by its granite soil and its moderate continental climate. From Livron to Montélimar, the vines give way to other crops.
South of the Donzère Defile, the vineyards are back in force on both banks of the river, south of Montélimar. The major stretches of vines on the right bank in the départements of Ardèche and Gard are joined by similar areas on the left bank, between lower Drôme and southern Vaucluse. The soil here is limestone covered in alluvia.
