The Alexander Valley AVA sits at the top of Sonoma County with about 15,000 acres of much prized vineyards. Within the 76,000 total acres of this AVA, there are a variety of microclimates supporting a substantial range of grape varieties. While Cabernet Sauvignon reigns supreme on the gravelly terrain of the valley floor, the Alexander Valley AVA also produces notable Chardonnay, Zinfandel, Merlot, and Sauvignon Blanc. Even some cooler-climate varieties, like Gewürztraminer and Riesling, have found a niche here in the shadow of Mendocino. Just enough coastal fog finds its way up the Russian River Valley to create cool evening and morning conditions. This, however, gives way to hot mid-day temperatures in what is overall a relatively warm growing area. Originally, the AVA was designated for the alluvial floodplain vineyards on both banks of the Russian River, but those boundaries have since been expanded to include mountainside vineyards.