Scientific knowledge of the complex environment in which the vineyards of Valais flourishes are needed to highlight the originality of this wine region and the personality of its wines. Extensive studies of soil and local climate have established a precise mapping of the entire vineyard. On this basis, municipalities have defined the most suitable varieties to soil and climatic characteristics of each plot. The varieties and areas suitable for the production of “Grand Cru” have been identified and defined with precision.