The Knights Valley AVA in Northern Sonoma County cuts through several miles of mountainous countryside, linking the Russian River Valley (and thus Sonoma Valley) with the northernmost reaches of the Napa Valley.
Its inland, sheltered location makes Knights Valley one of the warmest areas in Sonoma County. The vineyards are protected from the Pacific Ocean's cooling influences by the Coastal Ranges and the Mayacamas Mountains, and are too far north to benefit from the cool air and fog which roll up the valleys from San Francisco and San Pablo bays.
© George Rose
The Knights Valley AVA's eastern boundary is formed by the north-western edge of Napa County and the south-western edge of Lake County. The meeting point of these adjacent counties with Sonoma County is Mount Saint Helena (not to be confused with Mount St. Helens in Washington State). This ancient volcano towers thousands of feet above the Knights Valley vineyards, peaking at an impressive 4342ft (1323m). The mountain's eastern peak is the highest point in Napa County, and commands spectacular views down the Napa Valley to the south-east and Sonoma Valley to the south-west.
Knights Valley is surrounded by some of America's most prestigious viticultural real estate. Along its western side it abuts the Alexander Valley AVA, and its southern neighbor is Russian River Valley AVA. In fact, millions of years ago the Russian river ran straight through what is now Knights Valley, but its course was diverted by a massive Mount Saint Helena eruption. This left volcanic deposits and alluvial gravel soils on the valley floor, making it well suited to quality viniculture.
Well-drained soils, warm temperatures and high sunshine levels ensure Knights Valley is a prolific wine region, and that its most widely planted grape variety, Cabernet Sauvignon, achieves the full-bodied, ripe, chocolate flavors for which Knights Valley wines have become known. Beringer, one of California's oldest and most-respected wineries, has a significant presence in the Knights Valley AVA, and has made quality Cabernet Sauvignon since the early 1970s. The winery's Knights Valley Alluvium and Alluvium Blanc are two proprietary blends named after the alluvial soils here.
Although Cabernet Sauvignon is the undisputed king of Knights Valley, accounting for about two-thirds of the wine produced there, other full-bodied reds are also produced locally. These include Merlot, Syrah, Zinfandel and a small quantity of Mourvedre. Very little white wine is made in the valley, but a small quantity of Chardonnay, Semillon and Sauvignon Blanc is produced under the AVA title.