Cazadero is an unincorporated community and census-designated place (CDP) in western Sonoma County, California, United States with a population of 354 as of the 2010 Census.
Cazadero was the northern terminus of the North Pacific Coast Railroad, originally laid as narrow-gauge track in the 1870s. This railhead was fed by several smaller gauge systems dedicated to logging and networks of logging roads and trails which brought trees to Duncans Mill for processing and shipment south to San Francisco. Local legend holds that much of San Francisco was rebuilt after the disastrous April 1906 earthquake and fire using redwood and other lumber from the Cazadero area. Cazadero timbers are also known to have been used in pilings sunk to support the old (and now partially demolished) eastern span of the San Francisco-Oakland Bay Bridge.