Old Sonoma Road is an approximately five-mile highway located in the Mayacamas Mountains of western Napa County. The roadway is part of the original stage road which connected Napa Valley west to Mission San Francisco Solano as part of El Camino Real. Much of Old Sonoma Road was bypassed by the start of the twentieth century by way of Sonoma Highway. A portion of Old Sonoma Road over the 1896 Carneros Creek Bridge (pictured as the blog cover) was adopted as part of Legislative Route Number 8 upon voter approval of the 1909 First State Highway Bond Act. The 1896 Carneros Creek Bridge served as a segment of California State Route 37 and California State Route 12 from 1934 through 1954.
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