From OpenStreetMap Wiki
Could a highway=primary imply surface=paved? I'm guessing there are countries where it isn't so, so please mention here if you know a country where significant portion of primary roads aren't paved. Alv 09:52, 16 July 2009 (UTC)
- There are federal roads in Amazonia in Brazil which are unpaved or disintegrated over the years into dirt roads, for example BR-319 or BR-230 Rodovia Transamazônica. Maybe we should have an icon for unpaved roads (sand, gravel, dirt, grass)? In this case it could be red road but with dashed edges. I think it's not used in Mapnik.