Sonoma is the southwestern county and largest producer of California's Wine Country region, which also includes Napa, Mendocino, and Lake counties. It has 13 approved American Viticultural Areas and over 250 wineries. In 2002, Sonoma County ranked as the 32nd county in the United States in agricultural production. As early as 1920, Sonoma County was ranked as the eighth most agriculturally productive U.S county and a leading producer of poultry products, hops, grapes, prunes, apples and dairy products, largely due to the extent of available, fertile agricultural land, in addition to the abundance of high quality irrigation water. More than 7.4 million tourists visit each year, spending more than $1 billion in 2006. Sonoma County is the home of Sonoma State University and Santa Rosa Junior College.

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