Loire Valley (wine) a variety of limestone with excellent drainage that is known as tuffeau which is the same material used to build many of the famous Loire Valley Châteaux. The area around Chinon, Bourgueil and Saint-Nicolas-de-Bourgueil produces the majority of the Loire Valley's red wine based on the Cabernet franc grape—known in this areas as "Breton". The wines of the Chinon area are the softest and rich expression of the grape while the Bourgueil area produces more tannic and firm wines. The St-Nicolas-de-Bourgueil area produces the lightest colored wines. In the 19th century, the wines of the Chinon area were compared favorably
Loire sections are navigable: The French language adjective "ligérien" is derived from the name of the Loire, as in "le climat ligérien" ("the climate of the Loire Valley"). The climate is considered the most pleasant of northern France, with warmer winters and, more generally, fewer extremes in temperatures, rarely exceeding . It is identified as temperate maritime climate, and is characterised by the lack of dry seasons and by heavy rains and snowfall in winter, especially in the upper streams. The number of sunny hours per year varies between 1400 and 2200 and increases from northwest to southeast. The Loire Valley,