Chile´s principal viticultura zone occupies the Central Valley, which also is Chile´s agricultural heartland. The Central Valley is a plain located between the Andes Mountains and the Coastal Mountains, and starts just to the north of Santiago (to the north of Santiago there is no central plain and the Andes Mountains run across to the Pacific Ocean). This valley is then subdivided into viticultural zones (deonimnations) that roughly correspond to the watersheds of the major rivers that cross the country from the Andes to the Pacific Ocean. As such, the country´s viticultural denominations divide the country into blocks that are stacked one on top of the other running along the north-south axis.
The northern zones tend to be hotter and drier, and the southern zones tend to be cooler and wetter, with the difference in rainfall being more marked than the difference in temperature.
The difference between the zones governed by the north-south trend is usually much less dramatic that the differences found within each zone, which can described by their location along the east-west axis, and can roughly be divided into three zones: the foothills of the Andes Mountains, the central plain and the Coastal Mountain range, each of which brings its particular characteristics of breezes, fog, temperature, etc. There are some that would even go so far as to recommend scrapping Chile´s current denomination system and replace it with three zones: Andes, Central and Coastal.