Numbering of Freeway Lanes in California

Highway 110 Northbound from Downtown Los Angeles. California's oldest Freeway. Photo by California Department of Transportation.

Caltrans numbers each freeway lane from left to right. The “fast” lane is the number 1 lane. The “slow” lane (closest to freeway entrance/exits) is numbered according to the total number of lanes (anywhere from 2 to 6 in Los Angeles County).