Russian River Valley AVA

The Russian River Valley AVA is an American Viticultural Area in Sonoma County, California. Centered on the Russian River, the Russian River Valley AVA accounts for about one-sixth of the total planted vineyard acreage in Sonoma County. The appellation was granted AVA status in 1983 and enlarged in 2005. The area generally lies between Sebastopol and Santa Rosa in the south, and Forestville and Healdsburg in the north. The Russian River Valley has a characteristically cool climate, heavily affected by fog generated by the valley's proximity to the Pacific Ocean. The area is known for its success with cool climate varietals, notably Pinot noir and Chardonnay.
Despite its name, the Russian River Valley AVA does not cover the entire Russian River Valley-which extends north into Mendocino County, California and southwest all the way to the Pacific Ocean. Originally the river continued south and emptied into San Francisco Bay but during its history, for reasons not yet understood by geologists, the river changed course. The small segment of the river valley that makes up the AVA begins near Healdsburg once the river leaves the Alexander Valley region through a narrow gorge in the foothills of the Mayacamas Mountains. From there it extends south to the Santa Rosa Plains and Sebastopol and west to the towns of Monte Rio, Guerneville and Occidental. Within the boundaries of the Russian River AVA are the sub-AVAs Chalk Hill and Sonoma Green Valley. In 2003 the AVA was expanded to include 767 acres south of Fulton.

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