Sonoma County is in Northern California. It’s known for the Sonoma Valley wine region, as well as other notable wine making areas such as the Dry Creek and Alexander valleys. The city of Sonoma is home to the 19th-century Mission San Francisco Solano and the central, colonial-era Sonoma Plaza. Near Glen Ellen, Jack London State Historic Park contains the gravesite and cottage of the American author, plus many trails.Sonoma county is located north of the bay area. Sonoma county is north of Marin and Contra Costa counties, south of Mendocino County and west of Napa, Solano, and Lake counties. Sonoma county has 76 miles of Pacific Ocean coastline. Sonoma county also touches the San Pablo Bay at its most southern end.

According to the 2021 census the population of Sonoma county was close to 485,887. The largest city in Sonoma county is Santa Rosa. Santa Rosa is also the county seat. Other Sonoma County cities include; Cloverdale, Cotati, Healdsburg, Petaluma, Rohnert Park, Sebastopol, Windsor, and the city of Sonoma. Sonoma county is home to Santa Rosa Junior College and Sonoma State University.

Based on history, six nations have claimed Sonoma and parts of Sonoma county. The Spanish Empire founded Sonoma in 1542. England, Spain, the Russian Empire, the Mexican Republic and the California Republic all had claims, settlements, investments, missions, and/or territories in Sonoma. The city of Sonoma was the original county seat and home of the Bear Flag Revolt. Over time as Santa Rose grew in commercial importance, the county seat was moved.

In California’s Wine Country region, which also includes Napa, Mendocino, and Lake counties, Sonoma County is the largest producer. It has thirteen approved American Viticultural Areas and more than 350 wineries. Sonoma county produces hops, grapes, tree fruit, dairy, and poultry products. Large fertile tracks of land with irrigation from the Russian River, Petaluma River, and Laguna de Santa Rosa rank Sonoma county as the 32’nd highest county in agricultural production in the U.S.The voters have twice approved open space initiatives that have provided funding for public acquisition of natural areas, preserving forested areas, coastal habitat, and other open space. More than 8.4 million tourists visit each year, spending more than $1 billion in 2016.

State Route 1 is on the Pacific coastline from Marin County to Mendocino County. This stretch of popular coastline is considered the cleanest coastline in California. U.S. Route 101 is the main traffic road north and south. State routes 12 and 128 connected Sonoma county and Napa county wine country.