The pattern of growth in the San Francisco Bay Area was to be shaped largely by transit lines in the 1850s, wherever the opportunity for private gain appeared. With land and credit subsidies from federal and state governments, the Central Pacific built the transcontinental railroad. Transcontinental and local railroads helped open the entire western coast and the Bay region for settlement and promoted the development of Bay industry. Electric rail network, the Key System, maintained the East Bay's advantage over other Bay area suburban regions. The advent of automobile caused the downfall of the interurban electric railway, which in the early 20th century was the chief agent of population dispersal in the Bay Area. Completion of the Bay and Golden Gate bridges in the thirties initiated the slow decline of what had once been the world's most extensive ferry system. The state and federal governments took on a larger planning role in Bay region transportation projects after World War II. Rapid population growth and suburban expansion led to the construction of the mass transit system. BART construction in the 1960s was the first large-scale public transit to be built in the nation for nearly half a century. The consolidation of transportation which required mechanism for intergovernmental coordination was undertaken in the metropolitan regions in the 1970s.
