Côtes du Rhône is a region wide appellation within the Rhône Valley in eastern France. It applies to red, rosé and white wines, and includes more than 170 villages. The zone follows the course of the Rhône river southwards for 125 miles (200km) from Saint-Cyr-sur-le-Rhône to Avignon. A small proportion of the appellation's wines are white. However the classic Côtes du Rhône wine is a fruity, middleweight red blend based on Grenache, Syrah and Mourvèdre.

The Côtes du Rhône appellation was introduced in November 1937. Its purpose was to provide a catch-all title for good quality Rhône wines from the valley's lesser known and less prestigious viticultural areas.

In 1966, it was joined by the complementary Côtes du Rhône Villages AOC. This was granted to those Rhône villages deemed to be producing wines of consistently high quality. Above this, seven communes were allowed to attach their name on the label. This figure now sits at 18.

Gigondas (in 1971), Vacqueyras (1990), Vinsobres (2006), Cairanne (2016) have since been further elevated to have their own designation. In 2010 red wines from Rasteau were added to the existing appellation which had previously been applied only to vin doux naturel.

Some Côtes du Rhône wines are of extremely high quality. Some of the appellation's finest (and most expensive) wines command prices of more than $100 per bottle. Such examples include "La Bosse" by Domaine de la Vieille Julienne, and "Chateau de Fonsalette" by Chateau Rayas. Both of these come from producers based in Châteauneuf-du-Pape.

Some notable examples are made by a new wave of quality focused winemakers. The top-priced cuvées may also be sourced from high-quality vineyards outside the boundaries of more famous appellations.

The Rhône Valley climate varies measurably from north to south. The northern Rhône climate is cooler and more continental than the south – influenced more by the Alps than the Mediterranean. As a result, northern Côtes du Rhône wines tend to be slightly more structured and "serious" than those from the south.

The Mediterranean-influenced south enjoys a warmer, more stable climate with hot summers and mild winters. This contributes to richer, brighter, higher alcohol wines.

Grenache, Syrah and Mourvèdre grapes form the core of most red Côtes du Rhône wines. Here in the Rhône, Grenache almost always dominates the blend, particularly in the southern half of the Valley, where the vast majority of Côtes du Rhône wines are made. Syrah contributes structure and spicy notes, while Mourvèdre brings its dark, chocolatey notes and intense colour.

The Rhône Valley's north-south divide is reflected in Côtes du Rhône wine styles. It is even taken into consideration in the official appellation laws. These stipulate that Grenache should comprise at least 40 percent of any red wine made south of Montelimar – the transition point between north to south.

Those from the north contain more Syrah, and lean more towards a cool-climate style. They show good structure and notes of black cherry and fresh pepper (obvious examples include those from Guigal and Chapoutier). Those from the south favour Grenache, and a warmer climate style. This means higher alcohol and abundant fruit flavours of stewed blueberry, raspberry and plum.

Ten other varieties are sanctioned for use in red and rosé Côtes du Rhône wines, although they rarely represent any significant part of the blend. These are: Carignan, Cinsaut, Counoise, Muscardin, Vaccarese, Picpoul Noir, Terret Noir, Grenache Gris and Clairette.

The typical white Côtes du Rhône Blanc is relatively full-bodied, with notes of candied citrus fruits, acacia, herbs, straw, wax and possibly a hint of honey. The principal grapes used in white wines are Grenache Blanc, Clairette, Marsanne, Roussanne, Bourboulenc and Viognier. Interestingly, Ugni Blanc (better known for its role in Cognac) may also be used, as may Picpoul Blanc – of Picpoul de Pinet fame.