State Route 126 (SR 126) is a highway in Ventura and Los Angeles counties, California. The route runs from U.S. Route 101 in Ventura to Interstate 5 in Santa Clarita through the Santa Clara River Valley. The highway is an important connector highway in Ventura County, and serves as an alternate route into the Santa Clarita and San Fernando valleys, the High Desert of Antelope Valley, and Los Angeles.