The steepness of vineyards is given in percentage or degrees. However, the values given in many sources are often incorrect due to misrepresentation or confusion of percentage and degree. At 45°, this is the equivalent of 100%, whereas 45% is only 24°. The not possible 100° (overhang) would result in a purely mathematical 567%. An inclination of 90° corresponds to a vertical wall. The real maximum values of vineyards are about 75° (373%). In steep-slope viticulture on extremely steep slopes, conventional mechanical cultivation is often not possible, but only laborious manual work using special equipment. The vineyards there are usually laid out in terraces with retaining walls and stairs. For the mostly only manually possible vineyard maintenance, cable pull or special caterpillar vehicles must be used. Often, traditional systems such as single pole training (Moselle pole training) are common in such vineyards. In exposed areas, the spraying of plant protection products is carried out with the use of helicopters, as well as the transport of material, people and grapes during the grape harvest via monorack tracks.
Well-known steep-slope areas in Germany are in the growing regions of the Ahr, Baden(Engelsfelsen), Franconia(Kallmuth, Würzburger Stein), Middle Rhine(Bopparder Hamm), Moselle(Calmont, Doctor), Rheingau(Berg Roseneck, Berg Rottland, Berg Schlossberg, Höllenberg) and Württemberg in the Neckar Valley(Zuckerle).
In Austria, such can be found in southern Styria in the Sausalt Valley as well as in the Wachau region such as the Kellerberg. And in Switzerland they can be found in the two cantons of Vaud (Chablais, Lavaux) and Valais(Visperterminen).
The most famous steep slopes in France are in Alsace (in the Grand Cru location Rangen), as well as on the Rhône in the appellations Condrieu, Cornas, Côte Rôtie and Hermitage. In Italy, this includes areas in the Ligurian Cinqueterre area, in the Aosta Valley, Piedmont, South Tyrol and in the Lombardy Valtellina area; in Portugal, in the Douro port wine area; and in Spain, in the Priorato area.
See also under the keywords largest wine region/area of vines, highest vineyard, smallest vineyards & areas under vines, northernmost vineyard and southernmost vineyard and regarding superlatives in viticulture under records. A list of keywords relevant to vineyards is included under vineyard area.
Calmont: By H.Peierl - Own work, CC BY 3.0, Link
Kallmuth: VDP.DIE PRÄDIKATSWEINGÜTER
Zuckerle: By Berndt Fernow - Photographed by himself, in the public domain, Link
Kellerberg: Picture: © Robert Herbst POV
Côte Rôtie: From BlueBreezeWiki - Own work, CC BY-SA 3.0, Link