In which region are steeply sloped vineyards commonly found?

Steeply sloped vineyards are commonly found in the Sonoma Mountain region. This area is characterized by its mountainous terrain, which provides a unique microclimate and drainage that can be advantageous for grape growing. The elevation and slope enhance sun exposure and facilitate air drainage, which can contribute to the quality of the grapes. The steep slopes also mean that the vineyards often experience less fog than lower-lying areas, allowing for better ripening conditions for the grapes, leading to distinct flavor profiles in the wines produced.

In contrast, while Napa Valley, Coombsville, and Bennett Valley may also have elevated areas, they are not as predominantly noted for their steep slopes as Sonoma Mountain. Napa Valley, for example, is better known for its diverse range of vineyard sites, while Coombsville and Bennett Valley have their own characteristics but do not feature the same degree of elevation and slope found in Sonoma Mountain.