Center City Commuter Connection

The Center City Commuter Connection, commonly referred to as "the commuter tunnel", is a passenger railroad tunnel in Center City, Philadelphia, Pennsylvania, United States, built to connect the stub ends of the two separate regional commuter rail systems, originally operated by two rival railroad companies: the Pennsylvania Railroad and the Reading Railroad. All of the SEPTA Regional Rail lines except for the Cynwyd Line pass completely through the four-track tunnel, which contains two underground stations, Suburban Station and Jefferson Station, and the above-ground upper-level concourse for the east-west commuter lines serving 30th Street Station.
Suburban Station, located at 16th Street and JFK Boulevard, was the underground terminus of the commuter rail lines of the Pennsylvania Railroad . The Reading Company ran trains on an elevated approach above city streets into the Reading Terminal, located at 12th and Market Streets . The connection, the first of its kind in the United States, was built to allow trains to run through Philadelphia's downtown central business district, by uniting the commuter lines of the two rail systems.

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