[OSM-talk] definition of the main highway-tag

[Liz]

On Sat, 1 Aug 2009, James Stewart wrote:
> Classifying roads in central asia, it is easier, and makes more sense  
> in my opinion to use the highway ref in the administrative sense. Some  
> countries or regions have 5 or 6 main roads with are the national  
> trunk system. In places they are almost reduced to tracks through the  
> mountains, through which all traffic flows - it makes little sense to  
> mark then as a track though-

It won't ever be possible to have a system which covers everything clearly for 
everybody, so regional differences will exist.

A long standing convention on a printed Australian map is that a road which is 
unsealed is drawn with a broken line of the same colour and width as the road 
would have if it was sealed.

so you can say "that is the usual route, it isn't sealed" and then you may 
need to change travel plans because the road is closed completely or unusable 
for your vehicle type.