Directly east of Sonoma County lies Napa Valley. Most Napa Valley real estate is located in the county seat of Napa and these Napa Valley properties enjoy warm weather, an abundance of local wineries and proximity to San Francisco, Oakland and Sacramento. Strict county laws preventing urban sprawl have kept the region relatively underdeveloped, leaving large tracts of agricultural land separating Napa from the county's other towns, including Calistoga, St. Helena, Yountville and American Canyon.