Alsace is divided into two départements, Haut-Rhin and Bas-Rhin. This division provides a useful convention for quality of wine: generally the premier wines originate in the Haut-Rhin, and over two-thirds of Alsace’s Grand Cru vineyards are located in the département.
Geographically, Alsace is separated from the remainder of France by the Vosges Mountains in the west. The mountains provide a rain shadow effect; Alsace is one of France’s driest and sunniest climates. Colmar, capital of the Haut-Rhin département, is the driest city in France. The vineyards of Alsace exist in a thin strand along the lower slopes and foothills of the Vosges, and the exact aspect and location of each vineyard is of importance in this semi-continental climate.
The better vineyards enjoy southern, southeastern, or warm eastern exposures to maximize sunlight. However, despite their northerly location, Alsatian vines typically ripen with greater regularity than those in the Loire or northern Burgundy, due to the sheer number of sunlight hours in the summertime.