Compare rail density in Tokyo with Beijing, Shanghai, Hong Kong (scale is slightly off on HK). Only subways are colored--not regional railpic.twitter.com/k3oF8tP0Us
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Now at (roughly) the same scale, look at NYC, London, Paris, and Moscow--at least in Paris some regional rail is highlighted in color!pic.twitter.com/55elFfydoT
You can see that NYC has an astonishingly *dense* network of subway lines where they exist, but their coverage of the metro is lacking...
...you can also see Paris's rail network is about as dense as Tokyo's, tho less of their regional rail is held to subway standards afaik
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