St. Helena is a city in Napa County, in California's Wine Country, part of the North Bay region of the San Francisco Bay Area. The population was 5,814 at the 2010 census.
The city is the center of the eponymous American Viticultural Area which includes 416 vineyards encompassing 6,800 acres of vineyards. St. Helena is the location of The Culinary Institute of America at Greystone and a campus of Napa Valley College.