The middle portion of the Mississippi River watershed, rendered as an urban transit network. Why is the lower right section so empty, when it contains many tributaries of the Ohio, which is part of the Mississippi system, you ask? Well, I have specific rules as to how I draw these — the Ohio connects to the Mississippi just off the map. If a river’s connection is off the map, it’s not shown even if some of the body of the river would be in the map window. I want to emphasize the network and its connections, and to my mind showing rivers without showing how they connect distracts from this purpose.
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