Alsace is a complex and often poorly understood wine region. It's French, yet it has mostly German names and grape varietals, it has a complicated system of Grand Cru vineyard sites, and the styles of wine can vary greatly from one producer to another. To complicate matters further, while the region's famous late harvest (Vendage Tardive) and sweet dessert wines (Selection de Grains Nobles) are identified on the label, the "normal" cuvees are not, so unless one is familiar with a particular producer, there is no way to know if the regular wines will be dry, off dry or somewhat sweet, as the style (the level of residual sugar in the wine) is really up to each producer.
However, once explored, the wines of this picturesque and fairytale like region can be haunting. There are some good red wines produced (mostly Pinot Noir) but Alsace is all about its white wines. Refreshing Pinot Blanc, spicy Gewurztraminer, and rich Pinot Gris are all found here, but it is the majestic Rieslings that claim the top spot.
The Grand Cru system is complicated (there are fifty Grand Cru sites) and not all of them are equally worthy. However, if one learns the dozen or so best Grand Cru sites, you can expect to be rewarded with an intense and complex bottle of wine. Within the best grand Cru vineyards are also found the clos- walled-in vineyards- where the best vines are located. The most famous of these, Clos St. Hune (owned by the Trimbach family) in the Grand Cru Rosacker, is not only Alsace's most famous Riesling, but it is considered by most experts to be one of the world's greatest wines.
Alsace also is the source for very good sparkling wine: Crémant d'Alsace, usually made from a blend of grapes and with the same methods as in Champagne. A good Crémant, while never quite as rewarding as the best Champagne, has a wonderfully fresh acidity and good complexity, and often offer a great value.