Today, the two islands are physically connected by a train tunnel.
Smithsonian Mag
Eight days after dignitaries had cut the ribbon, engineers discovered that the train tunnel was too narrow and halted the service.
Times,Sunday Times
Notice how the brick-lined arcades match the train tunnel below.
Smithsonian
Why, though, do your ears go pop when you come out of a train tunnel?
Times, Sunday Times
They track her down to an abandoned train tunnel and search.
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