Unbuilt CA 157, CA 171, and CA 252

[Max Rockatansky]

Yesterday I spent some time on a Roadwaywiz webinar discussing the San Diego Freeway System.  One of the topics that came up was unbuilt CA 157, CA 171, and CA 252 which got me interested in a Paper Highways article for the San Diego Area.  CA 157, CA 171, and CA 252 were all added to the State Highway System as planned freeways in 1959.  CA 157 seems to have had the most substantial studies conducted as it's general alignment became fairly certain before the 1964 State Highway Renumbering.  CA 171 would have gone through part of Balboa Park and Switzer Canyon which probably didn't make anyone in San Diego happy.  CA 171 has a ramp stub which can be found on I-5 Exit 15B but the freeway was effectively blocked when San Diego purchased Switzer Canyon in 1987.  CA 252 was originally intended to be routed through National City but was shifted to San Diego circa 1966.  A stub ramp from I-805 was built to 43rd Street in the 1970s but the City of San Diego rezone the established right of away circa 1980. 

https://www.gribblenation.org/2020/04/paper-highways-of-san-diego-unbuilt.html