Covering a geographic area of around six-thousand hectares, but with only a minuscule fraction under vine, Rockpile AVA overlaps the larger [Dry Creek Valley](/ava/dry-creek-valley-ava) at its north west corner, with a section of land - around one-thousand hectares - falling under the umbrella of both appellations. In terms of its planted area of less than one-hundred hectares, Rockpile is amongst the smallest AVAs in [California](/region/california) and the entire [United States](/country/usa). However, what it lacks in size, in makes up for in quality, with a unique geology and microclimate described by critics and viticultural experts as one of the finest sites on the [North Coast](/subzone/north-coast) for cultivating the [Zinfandel](/zinfandel) grape. Elevation is key here. Almost all of the vineyards in Rockpile occupy plots above three-hundred metres, and AVA regulations state that grapes must come from sites at least eight-hundred feet (two-hundred-and-forty-four metres) above sea level in order to qualify for the label. This altitude, along with the somewhat inhospitable, rugged terrain suggested by the appellation’s name, and the influence of the Pacific Ocean and nearby Lake Sonoma, co-create a series of climatic conditions unique to these parts. Moderated temperatures, strong winds coming off the ocean and an absence of the fog so often associated with [North Coast](/subzone/north-coast) AVAs, affords Rockpile’s grapes a reliably long and steady growing season. Typically, they enjoy excellent exposure to sunshine with either a southwestern or a northeastern aspect, enabling the delivery two distinctly different wines from the same grape variety. The combination of shallow soils, steep slopes and a lack of moisture is conducive to low yields of high quality fruit. Established as an AVA in 2002, Rockpile is creating a name for itself on the [Californian](/region/california) wine scene. In addition to the intense, complex and flavoursome [Zinfandel](/zinfandel) wines most synonymous with the AVA, other varieties such as [Syrah](/syrah), [Petite Sirah](/petite-sirah) and [Cabernet Sauvignon](/cabernet-sauvignon) have also found success here on a small scale. Given the tiny size of the area under vine and the subsequently limited supply, Rockpile’s signature wines are difficult to obtain with most bottles snapped up by enthusiasts on release.