At Ocean Avenue, the K Ingleside line of the San Francisco Municipal Railway enters the median, remaining there until the boulevard ends several blocks later at St. Francis Circle.

[2] Between 1899 and 1915, the city of San Francisco built an "automobile boulevard" from the end of the existing Corbett Avenue (now Portola Drive) at Ocean Avenue[3] south past the Ingleside Race Track to the county line, where it continued to School Street in Daly City (then part of Colma).

To the south, Santa Clara County opened a section of the planned road past Stanford University on July 11, 1932.

1950[10] and still present) at Brotherhood Way and Alemany Boulevard in San Francisco[11] and a third (built by 1947) at Washington Street in Daly City.

)[14] The stub connection to El Camino Real was turned over to the city of South San Francisco to maintain as Hickey Boulevard,[9] which was later extended west to serve development.

[2] The state highway along Junipero Serra Boulevard, which had become Route 117 in the 1964 renumbering,[18] was turned back to San Mateo County in 1965.

[19] The state constructed the replacement freeway (I-280) in the mid-to-late 1960s and early 1970s,[10] and generally preserved the old boulevard as a frontage road north of Avalon Drive, though the grade separation at Washington Street was destroyed.