This essay examines the transition from a rail-based intercity transportation system in California in 1910 to a road/private auto-based system thirty years later, with hypotheses that the transition could be explained by either corporate and state decisions for supplying infrastructure or by public demand. The essay examines trends of automobile ownership, road investment, bus organization and service provision, intercity passenger rail service provision, and intercity rail revenues, both within California and to and from California in each of the three decades. It concludes that public preference for private automobility explains most of the transition but that unserved demand remained for fast passenger train service between the state's large metropolitan areas. Failure to serve that demand derived from California's legacy of popular disdain for the private railroad industry.