The City Hall Subway station in New York is supposedly shutdown for a long time now, unless you stayed on the 6 train for long enough. The station which I just knew was 100+ years old was under-construction to be restored as a pass-through museum still didn’t see light.
It took me a couple of days to understand how the NYC Subway system works. I do recall once getting on the 6 train by mistake and got to the Brooklyn Bridge which is presumably the last station on the 6 line. Well not quite the last one. If you stay on that train, what happens is that it goes for a U-turn around City Hall station and back at Brooklyn Bridge as the first station on the journey.
Try it next time you’re there! Link