Green Valley is a census-designated place in Solano County, California, located in the northeast corner of the San Francisco Bay Area. With a population of roughly 1,600 at the 2020 census, it is a small, low-density community that stands apart from the suburban development surrounding it. It lies approximately 38 miles from San Francisco and 45 miles from Sacramento, placing it squarely between the Bay Area and the Central Valley. The community's identity is rooted in its landscape. Green Valley occupies a rolling, rural valley of ranches, pasture, and oak-studded hillsides, and the name predates the modern CDP by more than a century, appearing as a township on an 1890 Solano County map. Agriculture, particularly ranching and grape growing, has long defined the area, with viticulture in the region stretching back to the 19th century. In 1982, the Solano County Green Valley American Viticultural Area was established, recognizing the valley as a distinct wine region within Solano County's broader grape-growing and ranching landscape. Green Valley has no dense downtown or commercial core. Homes and ranches spread across the hillsides and along rural roads, and residents rely on the nearby cities of Fairfield and Vacaville for shopping, services, and employment. This dispersed, semi-rural character is the community's defining feature, and the population remains small and stable. The community suits those seeking space, quiet, and a country setting while remaining within commuting distance of Bay Area and Central Valley job centers, as well as the wine country of Napa and Suisun Valley. It is a place defined less by development than by the open, working landscape it preserves, a rarity in a region otherwise marked by growth.