Rutherford is the geographic heart of Napa Valley. Approximately six square miles long and two miles at its widest point, this region has deep and well-drained gravel, sand and loamy soils, and moderate temperatures. Home to the famed "Rutherford Dust".
Howell Mountain overlooks St. Helena from the Vaca Range on the valley´s northeast side and encompasses 14,000 acres of which only 600 are vineyards. Known for its high elevation that ranges from 1,400 to 2,200 feet above sea level, the appellation enjoys sunshine, cool nights, and well-drained red volcanic soils.
Centered around the town of St. Helena, this appellation covers 9,000 acres along the flat narrow land towards the northern end of the valley. The region´s soils are a mix, beginning on the south and west borders with a more sedimentary, gravel-clay, with lower fertility and moderate water retention. Further north and to the east soils are prevalently volcanic in origin and are deeper and more fertile. This area is narrow and is almost entirely the product of river erosion.
Lake County is a mountainous region with elevations up to 2,600 feet. Its rocky red volcanic soils and cooler temperatures provide ideal conditions for growing wine grapes. This AVA has a colder winter and a longer growing season than any other wine growing region in California.