[1] The valley includes the communities of Santa Paula, Fillmore, Piru and the national historic landmark of Rancho Camulos.

Named for the Santa Clara River,[2] which winds through the valley before emptying into the Pacific Ocean between the cities of Ventura and Oxnard, the tourist bureau describes it as "Southern California's last pristine agricultural valley nestled along the banks of the free-flowing Santa Clara River.

It forms a connection between the high desert and the coast, which serves as a "wind-tunnel-like-corridor" for funneling Santa Ana winds, which spread wildfires.

[5] Further information: Great Flood of 1862 The failure and near complete collapse of the St. Francis Dam took place in the middle of the night on March 12, 1928.

Thomas Bard launched a campaign in the 1870s to build a road through the valley as he wanted to connect the new Hueneme wharf with ore mines in Inyo County[6] The valley is an exception to the post-war urban development that has almost entirely eliminated citrus cultivation throughout most of Southern California.