In spite of everything that maps can do, the ones I enjoy most are the simplest of all, those that reveal geography by stripping away all but some particular phenomenon and showing little or nothing more than where it exists. It’s the challenge of interpretation, or the self-satisfaction of recognizing something, or the imagining of a world to fill in the gaps, or something.

Every building in Montgomery County, Ohio

And so it was nice to run across this map of every building footprint in Montgomery County (Dayton), Ohio while idly browsing the “Maps” folder on my computer. I cranked it out from GIS data some six years ago. Give it a click for a large version.

Granted this map is more interesting if you know the area, but nonetheless it’s fascinating how much something like this can indicate about the patterns of human settlement in a typical American city. It’s not too difficult to see where settlement has followed or been bounded by highways and rivers. Industrial areas are discernible from residential areas, and city from suburb from rural. (By the way, this map only shows a sliver of Greene County—including my hometown of Beavercreek—where a good chunk of additional suburbia is located.) Owing to its simplicity, I believe this map shows urban patterns much more clearly than a satellite image or a road map.

If you’re familiar with the Dayton area, check out the patterns that probably confirm what you already know. See how to the north, settlement extends in spokes between the Mad, Stillwater, and Miami Rivers. Notice how immediately south of west Dayton, there’s hardly anything on the west side of the river. And look at the difference in suburban density on the west and east sides of Far Hills Avenue through Oakwood and Kettering.

If you’re not familiar with the Dayton area, the wonderful thing is that despite being nothing more than polygons, this map can probably teach you a bit about it.

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  1. Nice! All around from concept (strip away almost everything) to the specifics of this map that you describe (and others I noticed myself, like the lovely little Celtic knot curlicue of housing development streets at the edge of the map southeast of the oxbow downtown). Thanks!

    2 March 2010 @ 1:10pm

  2. someday Streets and Buildings will meet — would Buildings be little spoon or big spoon?


    3 March 2010 @ 2:51am

  3. Little spoon. They just like to be held.

    All Streets is the best map in this genre, and despite of all the amazing things Ben Fry does, it’s probably my favorite work of his. I would kill somebody to be able to do this with buildings for the whole country.

    Andy Woodruff
    3 March 2010 @ 9:11am

  4. I love it; Brilliant in its simplicity. Thanks for sharing :-)

    Shalom Craimer
    7 March 2010 @ 6:45am

  5. We make these all the time at school, though not usually at this scale. I’m an architecture student, focusing on urban design. These kinds of maps are called Nolli maps:

    7 March 2010 @ 4:43pm

  6. We have the same for Germany: all buildings + all roads.

    Stefan Knecht
    8 March 2010 @ 2:53am

  7. Robin, thanks for the Nolli link!

    Andy Woodruff
    8 March 2010 @ 5:01pm