Cartographer Kenneth Field is making a series of maps inspired by song lyrics about geography. Taking a cue from U2's song "Where the Streets Have No Name," he created this visualization of the 15 million unnamed street segments in the U.S.
As he explains at his blog, Cartonerd:
First, start with a nice healthy dataset of all streets in the contiguous USA and use some Geographical Information Systems savvy to process it. I'm fortunate to have access to the 2012 version of the Tom Tom data for North America which contains over 15 million street segments.
Second, apply a few of query analyses to extract any street segment without a name, discounting outliers like connectors, ramps, slip roads and such like. The result: a LyricMap of 3.5 million streets with no name, the beauty of which is that I don't need to worry about labeling because, well...there aren't any ...
The overall pattern suggests that it's streets in rural areas that have no name. Pretty much all the major cities appear dark indicating a low number of streets with no name. This makes sense...the dataset contains every road in the U.S. and many of them would be dirt tracks.