The West Side Ave. line
seems to come to a very abrupt and definitive conclusion at its last
stop, with a long drop down toward Newark Bay beyond.
Four or five miles pretty much directly ahead, beyond the Bay and
across marshland and industrial or formerly industrial old New
Jersey, Newark's City Subway starts at Penn Station, and plies
its own much older light rail route. The two systems are both under
the purview of NJ Transit.