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
Châteaux of the Loire Valley each year. Though there is no universally accepted definition for the designation, the main criterion is that the château must be situated close to the Loire or one of its tributaries (such as the Maine, Cher, Indre, Creuse or Loir). Châteaux further upstream than Gien are generally not included, with the possible exception of the Bastie d'Urfé for its historical significance. Châteaux of the Loire Valley The Châteaux of the Loire Valley (French: "Châteaux de la Loire") are part of the architectural heritage of the historic towns of Amboise, Angers, Blois, Chinon, Montsoreau, Nantes, Orléans, Saumur, and Tours along the