See the world’s subways evolve as time goes by
Alexander Rapp created a set of diagrams for subway systems around the world. Each shows the system’s geographic layout, all to the same scale, at various points in time. You can step forward and backward throughout history and see how, and when, each one evolved.
Click here or press the ‘a’ key to move all of the maps back five years. Click here or press ‘s’ to move ahead five.
Rapp chose which lines to show in each city by where there is frequent midday service, significant grade-separated areas, and closely-spaced stops (to exclude commuter rail) as of the end of the listed year. (Here’s more on his methodology).
His maps are 10 pixels per kilometer; I’ve selected a representative set of cities and shrunk Rapp’s maps to half their original size (5 px/km) so you can see more of them at once. You can look at the full size versions and all of the cities here.
Some of the maps aren’t available for all dates. The ones below don’t have maps for years ending in 5 at all, or only have them after some date.
What do you notice on the maps?