Napa County, located one hour north of San Francisco Bay (on the east side), encompasses Napa Valley, one of the world's most famous wine zones. As the Napa Valley AVA does include a valley situated between Yountville at the south to Calistoga to the north, many vineyards are sited on mountain ranges or in remote areas of the appellation. While wines from these sites can be labeled as Napa Valley, a few producers opt for Napa County as a designation. While it may be a proper geographic location, Napa County is not an AVA; that identification belongs to Napa Valley. (Wine/Appellations)