EUREKA, a city of California, U.S.A., 294m. N. by W. of San Francisco, on Humboldt bay, 2m. from the ocean ; a port of entry, the county seat of Humboldt county and the most western city in the United States. It is on the Redwood highway; is served by the Northwestern Pacific railway; and is a division point for the Pickwick stages, operating over the highway from San Francisco to Grant's Pass, Oregon. The population was 12,923 in 192o (24% foreign-born white), and was 15,752 in 1930 by the Federal census. Eureka is in a magnificent stand of redwood timber. Enormous quantities of redwood lumber are made in the saw-mills, and shipped largely to San Francisco, Hawaii, Australia and the Orient. Humboldt bay is the largest landlocked harbour between San Francisco and the Columbia river. Its traffic in 1927 amounted to 602,141 tons, valued at $18,087,733. At Arcata, on the northern arm of the bay, is the Humboldt State teachers' college. The Hoopa Valley Indian Reservation is 53m. N.E. by highway. When Humboldt county was organized (1853) Eureka was already the centre of an im portant lumber trade, chiefly in spars. The city was incorporated and became the county seat in 1856.