Located just to the north of the Russian River Valley AVA, Dry Creek Valley has two distinct climates. The valley floor area is low enough to be covered by the coastal fog common in the rest of Sonoma County, which causes the valley to be cooler and damper than the rest of the AVA. The other climate is the hillside area, which is high enough to perch above the fog line. Italian immigrants covered the hillsides with Zinfandel, which grows wonderfully and has become the one grape that is synonymous with the Dry Creek Valley name. Cabernet Sauvignon grown on the hillsides also produces robust, voluptuous wines, while white varietals such as Sauvignon Blanc cover the valley floor. The best vineyard sites have a soil mixture of well-drained gravel and red clay.