A project from Reddit user Bicapitate allows you to track NYC subway trains in real-time on a 3D-printed map of the island. The map shows the actual location of the subway trains using optical fiber and LEDs.

The map has colored lines that represent each of the transit lines and they are fitted with optical fiber lines along each of them. Each line is illuminated by RGB LEDs to indicate when a particular train is passing a location. The color of the track does not determine the color but rather the train does so one can tell when a particular train is running on a different track.

The project uses a Raspberry Pi 3B+ or 4B connected to RGB LED matrices which in turn connect to the map via fiber optics. The train data is retrieved open from an open server that the city provides. Locations are updated once every 30 seconds.

Check out the project on Reddit and an article on Tom’s Hardware.