The furthest westward point attached to land is Cape Mendocino at 40.434915 N 124.4076 W. The closest city is Ferndale at 40.5762 N 124.2639 W with a population of nearly 1400 http://en.wikipedia.org/wiki/Ferndale,_C��
Eureka, up in Humboldt County. Anything further west than Eureka is just a small town