The vast, sprawling network that is the New York City subway system started as one line, operated by the Interborough Rapid Transit Company and opened on October 27, 1904.
This old map shows the layout and expected travel times of the New York subway system as of 1906, from the Interborough Rapid Transit Company. The train rode the northbound track from the Fourteenth Street station to Grand Central, at 42 nd Street. (Alongside the early subway, New York City also had a network of elevated trains.)
Even on its first day of operation, the subway had both local and express cars, says a New York Times story from 1904, the beginning of a tradition that continues to confuse tourists to this day.
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