The boundaries of the Wachau has traditionally been the valley of the Danube between the village of
Melk and
Krems. Along with the
Kremstal and
Kamptal, the Wachau is one of the coolest wine regions in Austria. The climate of Wachau is influenced by the confluence of several weather systems including cool, moist air from the
Waldviertel forests of the northwest with warmer air coming from the east off the Pannonian Plain. This creates a
continental climate with marked
diurnal temperature variations that include a dramatic drop in nighttime temperatures. Along with the moderating influence of the Danube river, the Wachau has a
macroclimate which includes constant air and heat circulation, allowing for
sugars and
phenolic compounds to build up during the day but
acids and
aromas to be preserved by the cooler nights. This creates white wines that tend to be high in
extract and acidity.
Irrigation is often necessary during the peak months of the
growing season when yearly rain totals fall below . The
vineyard soils of the Wachau are varied but consist primarily of rock outcrops with occasional layers of
loess. The geography of the region is characterized by steep, rocky river banks (as steep as those found in the Mosel and
Côte-Rôtie) that have had vineyards
terraced into the hillsides. Higher up on the hills, the soils are rich in
iron deposits and contain mixtures of
gneiss,
granite and
slate. Closer to the river and in the flatter plains areas that dot the region, the soil is more
alluvial with loess,
sand and
gravel. The heart of the Wachau district is the
Vinea Wachau Nobilis Districtus which includes a strip of vineyard land that stretches from the western extremity of
Schwallenbach along the Danube through
Spitz,
Weissenkirchen,
Dürnstein,
Loiben and finally to
Mautern. There are over 900 named
vineyard sites in Wachau (known as
Rieden). Among the sites that may appear on Wachau wine labels those of the
Loibenberg, Kellerberg, Achleiten, Klaus and
Singerriedel are the most noted. ==Grape varieties and wine styles==