On 09/07/2008 16:03, Steve Hill wrote: > On Wed, 9 Jul 2008, Chris Hill wrote: > >> I would be strongly against a global change of highway=unclassified - all of >> the roads I have tagged as unclassified deserve to be so. I have been >> working partly on a very rural area, where many of the roads are >> unclassified >> (country lanes). To have to retag them from road to unclassified would be a >> very annoying waste of time. > > I agree that there are areas where the classifications are accurate, but > is there a good solution to the problem? > > I'm starting the discussion because I think there is a real problem here - > I don't have the solution, I'm hoping that a discussion might produce one. > :)
We've gone round and round the issue of what road classification means many times before. With a few dissenters, the consensus has generally been that you tag what you find on the ground. This sometimes contradicts the "official" classification. Some people who have had access to this information have used different tags to apply the "official" classification (though I do wonder about the copyright status of such information). While in the UK (in some other countries it is much less clear cut) this contradiction only happens occasionally for trunk (green signs), primary (A number on b/w signs) and secondary (B number on b/w signs) - e.g. the A road through Oxford discussed a while back - it is pretty much universal with the lesser roads which "officially" have a 'C' designation but which is virtually never signposted (or commercially mapped) as such, and is really a convenient shorthand for highway engineers. Even rural footpaths are numbered, usually uniquely per parish, but usually only evident when you come across a formal diversion/closure notice. So for the lesser roads, we have what amounts to a subjective choice: residential, tertiary, unclassified (and ok, track, service, byway etc, but those are perhaps a bit easier to be objective about). As it is subjective, I think you are wrong to change them except to maintain a consistency of approach in an area or where they are just wrong (signposted as a B road for example but not tagged as secondary). What I've done (and what a lot of others also seem to have done), for what is now getting to be a very large contiguous area - maybe 2,500 sq. km. centered on Cambridge(*) - is - tertiary for (a) unnumbered roads connecting settlements, except where they are so narrow that they really can't be considered as a reasonable connection even when they do actually join settlements (and yes, that's subjective) (b) unnumbered through or key distributors in urban areas (along with abutters=residential) - unclassified for (c) the rural exceptions to (a) (d) with abutters=something, for urban roads which are seriously non-residential (e.g. public roads through an industrial estate) - residential for everything else public, surfaced and unnumbered in an urban area, in which I include possibly only partly residential. The break between residential and unclassified (or between tertiary with and without abutters=residential) is not visible on the renderings, but I've felt it is important to leave it in as I think it is a potentially useful distinction for e.g. defining an "urban envelope" or applying a reduced default speed limit for journey planners. IMO, this gives a good indication of a hierarchy in rural areas which continues in and within urban areas. This leads to a nice rendering, but it isn't just tagging for rendering, it genuinely reflects the hierarchy. OS Landranger maps have a similar approach, based on width less than 4m (by memory). While my estimate of width is subjective, not measured, I'm essentially doing the same thing (though sometimes I am inclined to make a somewhat wider road unclassified if it goes nowhere). David * http://www.openstreetmap.org/?lat=52.1543&lon=0.0771&zoom=13&layers=B00FTF - the area now contiguously complete to the "all streets with names plus main POIs" level is mostly rural, covers around 150 villages, 6 market towns and one modest city, and extends roughly west as far as Papworth Everard, south to Ashwell, Royston, Barley and Saffron Walden, est as far as Moulton east of Newmarket and north as far as Littleport north of Ely and the Ouse south west of Ely. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk