State Route 163 (SR 163), the Cabrillo Freeway, is a state highway in San Diego, California. It is an 11.088 miles (17.844 km) stretch of freeway which was once the southern end of U.S. Route 395, the San Diego portion of which was eliminated in 1972. It begins in Downtown San Diego just west of an interchange with Interstate 5, extending north to its terminus at Interstate 15 at the south end of Miramar.

The southernmost 2.5 miles (4.0 km) of Route 163 passes through Balboa Park and under the Cabrillo Bridge. Emerging from Downtown San Diego on an intersection on Ash Street, it crosses Interstate 5 before entering Balboa Park. The section of Highway 163 south of Interstate 8 through Balboa Park is not Interstate standard, featuring a wide, grassy median with many mature trees. It has only four lanes for the most part and has several sharp curves (for a freeway). In an effort to improve safety along this section, wooden guardrails with steel reinforcement were installed in December 2004 on either side of the grassy median.[citation needed] The section of Highway 163 north of Interstate 8 is an Interstate-standard, eight-lane freeway. Just north of the interchange with I-8, the expressway treks north, climbing uphill from Mission Valley to Linda Vista, where it has an interchange with Genesee Avenue. After a northbound only exit with Mesa College Drive / Kearny Villa Road, the interchange with Interstate 805 is northbound only in the northbound direction and southbound only in the southbound direction. In Kearny Mesa, the freeway has interchanges with Balboa Avenue, and Clairemont Mesa Boulevard, in which between the two interchanges, it gains a frontage road on both sides of the freeway. Following the Clairemont Mesa Blvd. interchange, it heads north to CA 52, where it forms one part of one of the biggest bottlenecks in San Diego County. The freeway then heads north to Kearny Villa Road, which was a former route of Interstate 15, before terminating at the current I-15 near Miramar and the southern terminus of the reversible lanes of I-15.

This route is part of the California Freeway and Expressway System and is designated a State Scenic Highway.

The southernmost portion of the highway, running through Balboa Park, was designated a California Historic Parkway in 2002. This segment, which opened in 1948 as part of U.S. Route 395, was the first freeway in San Diego County and one of the first in California.[citation needed] This stretch of road has been called one of America's most beautiful parkways.

There were previously southbound entrances at Quince and Richmond Streets, but these have been closed for several years. The single-lane bridge at Richmond Street which allowed this entrance still exists, but is closed to traffic, and the remainder of the ramp has been demolished.

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, and do not necessarily reflect current mileage. The entire route is in San Diego, San Diego County.