New York's subway system is so old that many of its parts are no longer manufactured

The New York City subway is one of the longest, busiest, and oldest systems in the entire world.

You'd expect something that sees nearly two billion annual riders to run on state-of-the-art equipment, but it doesn't. In fact, a lot of the components that make up the subway's signal system are so old that they're no longer manufactured — many of the pieces were originally built in the early 1900s. 

So if they can't buy new equipment, how do they keep the system running? We visited the MTA's signal shop in Inwood, Manhattan to find out. 

Learn more by visiting the New York Transit Museum.

Story and video by Ben Nigh

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