Siskiyou County /ˈsɪskjuː/ SISS-kew is a county located in the northernmost part of the U.S. state of California. As of the 2010 census, the population was 44,900. Its county seat is Yreka.
Siskiyou County is located in the Shasta Cascade region along the Oregon border. Because of its outdoor recreation opportunities and Gold Rush era history, it is an important tourist destination within the state.
Siskiyou County was created on March 22, 1852, from parts of Shasta and Klamath Counties, and named after the Siskiyou mountain range. Parts of the county's territory were given to Modoc County in 1855.
The county is the site of the central section of the Siskiyou Trail, which ran between California's Central Valley and the Pacific Northwest. The Siskiyou Trail followed Native American footpaths, and was extended by Hudson's Bay Company trappers in the 1830s. Its length was increased by "Forty-Niners" during the California Gold Rush.
After the discovery of an important gold strike near today’s Yreka, California in 1851, prospectors flooded the area. This was described in detail by Joaquin Miller in his semi-autobiographical novel Life Amongst the Modocs.