When making this visualization I wanted to know what it would look like if I were to take a map of Boston and choose a color for each point depending on which subway stop was most convenient from that point. Luckily, a Voronoi Diagram is perfect for this sort of visualization.

Luckier still, the city of Boston has a surprisingly well-documented API and there are many publicly available datasets regarding the Massachusetts Bay Transit Authority (MBTA).

The data I used for this visualization can be found here.

The Google Maps layer underneath this visualization is fully interactive, so you can drag the map and click on available locations to get more information. As you zoom in, more subway stations will be labelled on the map. The circles inside each polygon are there as a reference for the actual location of the subway station, according to my data. The colors of the circles and the polygons indicate the color of the trains that stop at the closest station (if you are unaware, the four main Boston subway routes are the Red, Orange, Green, and Blue Lines).