Humboldt -- U.S. County in California Population (2000): 126518 Housing Units (2000): 55912 Land area (2000): 3572.487601 sq. miles (9252.700018 sq. km) Water area (2000): 479.737120 sq. miles (1242.513384 sq. km) Total area (2000): 4052.224721 sq. miles (10495.213402 sq. km) Located within: California (CA), FIPS 06 Location: 40.747403 N, 123.988265 W Headwords: Humboldt Humboldt, CA Humboldt County Humboldt County, CA