Major stream systems of my beloved home of Michigan, rendered as an urban transit network. I originally intended to do one map per state (or group of states, for the smaller ones), starting with Michigan, but I decided later to use watersheds, rather than political boundaries, as the basis for a map series.
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somethingaboutmaps 
Very cool Michigan map. I like the idea of doing maps for all the Great Lakes. I would like to see a more detailed map of Southeast Michigan, especially Detroit. You can’t forget about the Rouge River or Conner Creek! Perhaps in the future?