Champagne is the coolest of France's great wine regions, lying about 90 miles northeast of Paris, and the only place whose sparkling wine may be called Champagne.
Aromatically, texturally and in flavor it is one of the most distinct wines in the world, the product of two natural assets: an iffy, marginal northerly climate (the average temperature is a bare 50°F / 10°C, at the very limit of photosynthesis) and famous white soils that are more than 75 percent limestone, much of it a porous chalk that drains well yet stores water and suits high-acid grapes.
Only three varieties may be used — chardonnay (the only white, and the sole grape of blanc de blancs), pinot noir (the more revered red, giving body, structure and aroma), and pinot meunier (a supple, fruity clone of pinot noir, the least ageworthy, used mainly in nonvintage blends).
ALL CHAMPAGNES ARE BLENDS — of as many as a hundred separate still 'base wines', often from several years and held-back reserve wines — and among the Champenois the art of blending (the assemblage) is considered paramount.
Champagne is made by the méthode champenoise / méthode traditionnelle: still base wines are bottled with a liqueur de tirage (sugar + yeast) to trigger a SECOND FERMENTATION inside the sealed bottle, which traps carbon dioxide as dissolved gas — the future bubbles.
The wine then rests for years SUR LIE (on the spent yeasts); through AUTOLYSIS the yeast cell walls break down, lending a creamy texture and complexity, so a great Champagne is at once lightning-crisp from acidity and lusciously creamy.
The yeasts are removed by riddling (rémuage) and disgorgement, after which a dosage (liqueur d'expédition, sweetened reserve wine) sets the sweetness style — from bone-dry brut nature and extra brut up through the now-dominant brut (<12 g/L sugar) to the rare sec, demi-sec and doux.
All of Champagne is a single appellation, but its 320 villages are ranked Grand Cru (17 villages), Premier Cru (42 villages) or Cru, with every vineyard in a village sharing the village's rank; its five vineyard areas are led by the Montagne de Reims, the Côte des Blancs and the Vallée de la Marne.