Santa Susana Pass, Mountain pass in Simi Hills, California, United States

Santa Susana Pass is a mountain crossing in the Simi Hills that links the San Fernando Valley with Simi Valley through State Route 118. The area features sandstone cliffs, scattered large boulders, and open grasslands dotted with oak trees across its landscape.

The pass lay at the junction of Tongva, Chumash and Tataviam lands and was crossed by their trail for an estimated 8,000 years. The Spanish Portolà expedition crossed on January 15, 1770. In 1859 the legislature funded a stagecoach road; the first Butterfield overland mail stage ran through on April 6, 1861. Southern Pacific opened three railroad tunnels in 1904.

The name Simi Pass was used from 1857, when the Los Angeles Star reported the capture of the outlaw Juan Flores there; Santa Susana Pass appeared in the Los Angeles Herald on 18 September 1887. From the 1920s to the 1950s the pass appeared in Westerns shot at the Spahn, Iverson, Bell Moving Picture and Corriganville movie ranches. The Spahn Ranch, near the top of the Devil's Slide, later housed the Manson Family.

Several hiking trails give visitors access to explore the rock formations and open landscape, with parking areas near the main trailheads. Plan to visit during cooler months since the area receives full sun exposure and carrying water is essential for any visit.

Three railroad tunnels were blasted through the rock in the early 1900s to create a continuous rail link between major cities. These passages remain visible today and stand as a reminder of the engineering effort required to cross this barrier.