Siskiyou County is a largely rural and sparsely populated mountainous area, with small towns and cities separated by long travel distances. The county is bordered by Oregon to the north and Shasta, Trinity, and Tehama Counties to the south. Mount Shasta, located in the center of the county, is the fifth highest peak in California. Population grew in the mid 1880’s during the California Gold Rush, while tourism increased in the 1880’s after the construction of the Central Pacific Railroad. Siskiyou County is home to several Native American tribes, including the Klamath, Karuk, and the Shasta Indian Nation.

Interstate 5 (I5) runs north to south through many major communities in the county, including Dunsmuir, Mt Shasta, Weed, Yreka, and Hornbrook. State Route (SR) 97 connects to the northeastern portion of the county, Macdoel and on into Oregon, while SR 96 connects to the western portion, Happy Camp, along the Klamath River. In the southern area, SR 89 travels from Mt Shasta southeast to McCloud and on into Shasta County, while SR 3 connects the I5 corridor with Scott Valley area to the southwest and on to Trinity County.