Anderson Valley is a sparsely populated region in western Mendocino County in Northern California. Located approximately north of San Francisco, the name "Anderson Valley" applies broadly to several rural, unincorporated communities in or near the alluvial terraces along Anderson Creek and other tributaries to the Navarro River. It is named after William Anderson, an early European settler to the area. Geography The name "Anderson Valley" applies to a region stretching from Boonville (located on Anderson Creek) and Philo (located on Indian Creek) to Navarro (located on Soda Creek). Rancheria, Anderson, Indian and Soda creeks are tributaries to the Navarro River, which flows north and west through the coastal range to the Pacific Ocean; Dry Creek flows south into the Russian River watershed in Sonoma County. The main stem of the Navarro River begins less than a mile south of Philo at the confluence of Anderson Creek and Rancheria Creek. The mouth of the Navarro is south of Mendocino, California. Encompassing , the Navarro River watershed is the largest coastal basin in Mendocino County. The area is not seismically active, though a minor fault runs along the Valley floor. The climate is tempered by cool marine air. Steep hills and mountains surround rolling to nearly level alluvial terraces. The dominant natural vegetation is a mixed forest of Coast Redwood, various native oak varieties, and Douglas fir. Elevation ranges from sea level to . The average annual precipitation ranges . The average annual temperature is about , and the average frost-free season ranges from 220 to 365 days. Towards the coast the summers are cool and moist with frequent fog, while the interior Anderson Valley proper features a warm to hot summer climate similar to nearby interior regions, with daytime highs occasionally in excess of . History Early Native American inhabitants of Anderson Valley were speakers of two of the seven Pomoan languages. The Late Pomo of what is now the Yorkville area spoke the Central Pomo language. The Tabahtea (Tah-bah-tay) Pomo of the Boonville area west to Navarro spoke the Northern Pomo language. These residents occupied nineteen known village sites, with an estimated population of 600 in 1855. The early European American settlers of Anderson Valley arrived after 1850. They practiced subsistence farming and expanded into resource extraction economies based on timber harvesting and livestock ranching. Some of the first European American settlers included Henry Beeson (who took part in the