This is clearly traceable to TIGER, the US Census data that most map providers use as the bedrock of their map data in the rural US, yet was never meant for automotive navigation.<p>TIGER classes pretty much any rural &quot;road&quot; uniformly - class A41, if you&#x27;re interested. That might be a paved two-lane road, it might be a forest track. Just as often, it&#x27;s a drainage ditch or a non-existent path or other such nonsense. It&#x27;s wholly unreliable.<p>You can see this in OpenStreetMap easily. Navigate to the backwoods and look at the road types. It&#x27;s predominantly highway=residential, the road type that A41 was mapped to in the TIGER import. highway=residential is usually meant for city streets and suburban residential roads. Not this.<p>So: help! I&#x27;ve genuinely spent weeks on this but it&#x27;s a massive job. Paved road? Reclassify it as highway=tertiary (wider with centreline) or highway=unclassified (narrower, no centreline). Gravel or dirt graded road? highway=unclassified, surface=gravel (or =dirt). Rough, not recommended for most cars? highway=track. Genuinely a paved residential road? Keep the highway tag as it is, but delete the tiger:reviewed=no tag. Nothing there at all? Just delete it.<p>(My particular interest in this is bicycle routing. Bike routing usually prefers the smallest paved roads in the grid. It breaks if those &quot;paved roads&quot; are impassable desert tracks in reality. I take a very conservative view for my site, <a href="http:&#x2F;&#x2F;cycle.travel&#x2F;map" rel="nofollow">http:&#x2F;&#x2F;cycle.travel&#x2F;map</a>, precisely because I&#x27;m anxious about situations such as that described in the Ars article.)