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Rewrite, Aug 2009

After an extended discussion on the talk list, I've attempted a rewrite to clarify how this tag seems to be used in urban and rural contexts, and the situations where other tags seem to be preferred. I've also struck out some duplication, and an extended paragraph on the distinction between unclassified and track (replaced by something a little more succinct). The struck bits will get properly deleted in a day or two if no-one squeals.

--RichardMann 15:09, 6 August 2009 (UTC)

Martin/Dieter wrote on the talk list: actually there are 3 things in the main definition (1st phrase) I don't consider good ideas: "Public road without (official) classification, primarily for access to properties, typically paved, non-residential."

1. classification is not unambiguous (what kind of classification). What about countries with classification for more kind of streets? Shall they invent another highway-class for small roads, because there is a classification for smallest roads in there country? 2. streets primarily or solely for access to properties are IMHO tagged as service 3. "typically paved" is a definition that depends strongly on context, and in wide parts of the world I suppose it not to be true

The page has been amended to take on board points 1&3. I don't agree with point 2. Service is used in for roads with (in towns) no pavement/sidewalk, and exclusively for access to a limited number of properties.

--RichardMann 16:46, 6 August 2009 (UTC)

I imagine I am not alone in using unclassified in exactly the manner struck out on the first line. Originally this tag was probably conceived to match roads shown in yellow on the OSGB 1:50000 map (I think called unclassified on the legend). Therefore many ways with this tag in the UK at least will accord EXACTLY with the struck out definition. Ideally the wiki should describe usage of tags on OSM, not various opinions on talk. The tag may be poorly named, and interpreted in a huge number of different ways, but I think we can live with it for all its faults. Changing the wiki to reflect some viewpoints merely reduces the usefulness of the wiki, which should document actual usage. (Note that in UK parlance residential roads are also unclassified, and logically are a subset of this group: see below). SK53 18:09, 6 August 2009 (UTC)
I think what happens round here (Oxfordshire) is that we use tertiary for OS wide yellows (more than 4m) and unclassified for OS narrow yellows (less than 4m). I thought I was trying to write that in a way that was clear and could be used internationally without reference to "classification", which obviously isn't going to travel well. Are you using unclassified for both wide and narrow yellows? Cos if we can't even agree in the UK, no wonder the rest of the world can't make sense of it!--RichardMann 22:00, 6 August 2009 (UTC)
Saying "Ideally the wiki should describe usage of tags on OSM, not various opinions on talk" is all well and good, but the whole point of the mailing list discussion is that it isn't used the same way everywhere in OSM. How is the wiki supposed to document "actual usage" when that varies from place to place? I think that documenting what it means for the UK is basically where the confusion started, because that description has a different meaning to people in other English-speaking countries (and ones where English isn't the major language). -- James Livingston
You asked, "How is the wiki supposed to document actual usage when that varies from place to place?". Quite simply - explain the situation honestly. See my comment below. -- Waldo000000 00:20, 11 August 2009 (UTC)
Surely, given that the default colours in OSM follow Landranger maps, that would be highway=tertiary. We all know there are highway=unclassified roads that would be better off with highway=tertiary or highway=residential, but the wiki really should be encouraging instead of discouraging them from being tidied up. --Wynndale 17:42, 8 August 2009 (UTC)

Presently IMHO it's an absolute mess. Try reading the whole page through once, then see if you can explain to someone what it means. Or better yet, get a non-OSM'er to read it and see if they understand. Here's another idea: there appears to be several distinct definitions of the tag in current use, according to talk and talk-au mailing list discussion e.g.

  1. urban roads in industrial areas less important than highway=tertiary
  2. "something bigger than highway=residential but smaller than highway=tertiary"
  3. rural roads less important than highway=tertiary
  4. "a road equal to a residential road, but outside residential areas"; "a road roughly equal to residential but without people living there"
  5. "the lowest street/road in the interconnecting grid, be it in urban or rural areas"
  6. in the UK: "roads shown in yellow on the OSGB 1:50000 map" (SK53, above) OR "OS narrow yellows (less than 4m)" (RichardMann, above) --22:30, 6 August 2009 (UTC)

Rather than trying to unify the different usages into one big confusing mess, maybe it would be better to separately explain each current usage? i.e. "This tag is used if the road is A or B or ...". This more closely reflects reality and IMHO will not be any harder to read than the current mess. This could also lead the way to improve the situation in future.

--Waldo000000 22:13, 6 August 2009 (UTC)

Poor Name

This strikes me as a very poor tag, almost guaranteed to cause confusion. Surely someone can come up with a better (and less UK-centric) alternative. (Previously unsigned comment 10:42, 6 December 2008 Mappo)

I agree. I suggest "highway=rural". Especially considering where United States roads tagging says "Most roads in most counties should be labeled unclassified (or residential in urban neighborhoods)." If most roads in most counties should be labeled a certain way, doesn't that constitute a classification of some kind? To classify something as "unclassified" is confusing and potentially counterproductive. (While it may seem counterproductive to change an existing policy, most rural roads imported from TIGER need to be changed anyway, as they're currently tagged "highway=residential".) Vid the Kid 05:37, 13 January 2009 (UTC)

I also agree it's UK-centric, but we probably need to clarify the usage first. Rural doesn't quite work because it's sometimes used in towns.--RichardMann 13:37, 6 August 2009 (UTC)

highway=minor sounds good to me, it's not UK-centric and doesn't matter if it's urban or rural. --Hawke 22:42, 6 August 2009 (UTC)

I agree it's a bad name since people often seem to confuse it with highway=road (unknown). // Liftarn

Hopefully Richard's and others' revisions and the big clarification edit I just did should have synthesized a better and more international explanation of what this thing is and where it should/can be used - even if the definition is partly by exclusion. I've added a few words explaining the historical reasons for the choice of word, bumped the warning about highway=road to the top of the page, and tried to gloss, tabulate and explain various things cleanly. Of particular note, highway=unclassified is not a UK-specific tag. Everyone is free to use it, of course. Moreover, it never mapped cleanly to a single UK road category in practice since in the UK the most minor classifications are not typically written on signs (see and thus have been unavailable to mappers. Fully acknowledge it's a pretty awful name, but IMO it's best to leave the data we have intact and just explain why it's weirdly named. --achadwick 18:52, 15 December 2011 (UTC)

New suggestion 2014:12

"Minor" (type) is a better suggestion but I'm going to make a further suggestion of 'Capillary'.

Clearly 'unclassified' is not a classification - and should only be used where it is not known the road's classification.

Pmailkeey (talk) 12:53, 4 December 2014 (UTC)

UK Unclassified County Road

In the UK, unclassified road is no longer a legal term, but Unclassified Country Road is, so as there is no specific entry for Unclassified County Road, UK users (like me!) might be tempted to apply unclassified road, which would be bad as it is clear that this is meant to reflect a road that is passable by a standard car. Most unclassified county roads need a 4x4, but typically are good horse or bike tracks. This link us useful Planning Inspectorate ruling IanMSpencer 10:16, 26 April 2010 (UTC)

The link is dead now, but if this is the same thing as a "green lane", that should be covered now. The main page currently suggests using highway=track instead, and I've tweaked the description slightly, calling them "unsurfaced" and making it clear that the sensibly-driveable ones are still highway=unclassified + suitable surface tag. --achadwick 18:32, 15 December 2011 (UTC)


The standard Mapnik rendering for unclassified roads seems unnecessarily wide at high zoom levels, making them look far wider than they really are, and obscuring roadside detail. A typical unclassified road is about 4m wide, but at zoom 18 it looks like 8m wide, at zoom 17 like 12m, at zoom 16 like 20m, and so on. It's especially noticeable when comparing them against grade-1 tracks which are shown as a thin brown line; often there's little difference between the two in reality. I don't know if I'm raising this issue in the right place, but it would be good to hear people's opinions at least. Tongro 00:46, 28 January 2011 (UTC)

"Primarily for access to properties" is wrong. Reword or remove.

Resolved: Seems to have been done, or perhaps I was just misreading it --achadwick 18:21, 15 December 2011 (UTC)

Suggest removing or changing the "primarily for access to properties" wording. It contradicts the "non-residential" in the ValueDescription box. --achadwick 17:35, 15 April 2011 (BST)

Page cleanup, December 2011

I've just done a big reordering and cleanup of the main page, which I nevertheless hope doesn't change the intent and meaning of anything. It was started in part because one user seems to have got the impression that this tag was UK-specific, which isn't the case, but it seems to have turned into a more thorough do-over. Specifically:

  • Intro paragraph: expanded, added introductory sentence,
  • Flagged the warning re highway=road in the very first section.
  • Section on urban vs. rural.
    • Reordered the criteria physical-first,
    • Tried to be vaguely international, but we probably still need to call out exceptions: countries where there's a specific lowest-level classification available to mappers and this drives all OSM tagging.
  • Section on useful supplementary tags
    • Footway is now sidewalk. It's a general highway thing, but I didn't want to remove any guidelines at all in this pass, so I documented old vs. new.
    • Tabulate and consolidate.
    • Reiterate the urban vs. rural split of these ways.
  • More sections
  • International usage section
    • Actually a rejig of the old "How to distinguish highway=unclassified from highway=track with tracktype=grade1, and from highway=service" section. Usage had clearly drifted over time to be a comparison of just German and British usage.
    • Expanded the para to summarise the inglorious and confusing history of the tag value in the GB section.
    • German section is still only a link :( De-englisched the para a bit.
    • Clarify intent. The tag should be good for all countries if properly defined.

Could people review please, and work on anything else that needs to be said?

--achadwick 19:20, 15 December 2011 (UTC)

This page is in contradiction to Key:highway

Resolved: All references to physical characteristics as globally-applicable criteria have been removed. Those references to physical characteristics which remain are explained as examples in the context of determining where the road sits in the local transportation grid. --achadwick 14:09, 4 May 2012 (BST)

The page Key:highway states

The highway tag is the primary tag used for highways. It is often the only tag. It is a very general and sometimes vague description of the importance of the highway for the road grid.

... the consensus is that the highway tag is for making a general description of the importance of a highway in the street grid. This gives the user of a highway more useful information than a legal classification or by physical characteristics, which depend highly on the area (amount of traffic, density, wealth).

To describe more details of the highway it is strongly recommended to add physical and legal attributes like lanes=*,surface=*, maxspeed=*, maxheight=* and width=*. ...

In addition there is a useable and clear differentiation to highway=residential: highway=residential

This tag is used for roads accessing or around residential areas but which are not a classified or unclassified highway.

This is a useful guideline if you are not sure whether to use "residential" or "unclassified" for streets in towns:

  • residential - street or road generally used only by people that live on that road or roads that branch off it.
  • unclassified - a road that has no administrative classification ref=*. Unclassified roads typically form the lowest form of the interconnecting grid network.

These basic definitions are already in use for quite a while and unchanged at least 2 years. And for me they were clear enough to classify thousands of highway kilometers.

This page tries to define unclassified roads by their physical characteristics like width and surface instead of their importance for the grid. But these "definitions" remain vague. I think it's impossible to come up with such definitions which are globally valid and precise enough to be useable. And more important: it's wrong to classify a highway based on its physical characteristics.

Even in the same country you can find unclassified or even higher classified highways which are unpaved and you can find tracks which are paved. This fact is even written on the referenced page Countryside. You can find also industrial and urban areas where unclassified highways used mainly and heavily by local traffic not only are paved but have physical characteristics of a highway=motorway.

Unfortunately I wasn't able to find proposal, discussion and voting related to this page. I would greatly appreciate to get pointed to it.

There will probably be none since this tag has been here since the beginning of OSM, I think. The proposal/voting process should be considered broken, although sometimes the discussions are worthwhile. --achadwick 21:37, 18 December 2011 (UTC)

I propose to delete all text trying to define unclassified based on physical characteristics. And we'll see how much is left which isn't written already on other pages.

By the way it's bad style and not the way how OSM is succeeding just to delete contributions of others. Be aware this can happen to your contributions as well.

Willi2006 06:27, 17 December 2011 (UTC)

I find the current text not as "defining by physical", but as giving a set of questions or clues a mapper can consider when a bit unsure between any of tertiary/unclassified/residential/track. Nobody has yet built a magical importance assessment apparatus, so the classification is always (well, with motorways and the like excluded) somewhat based on a comparison of the road in question with other roads nearby, based on both the network, the signage and the physical form. There's no globally typical physical description of a unclassified road, but within a region there's a typical physical difference between unclassified and tertiary (and track) - with exceptions, as you note. Somebody could do a complex flowchart for choosing the highway value :) Alv 11:15, 18 December 2011 (UTC)

I can't understand what you're getting at here, Willi2006. You suggest deleting anything that seems like a physical criterion, and seeing what's left. Do you think this tag is worthwhile or not? If you still think it is somehow only applicable to some countries and not any others, please tell us what those countries are and what the differences are.

I think Alv is right: physical characteristics *can* be used locally for deciding what OSM level a road is, based on your personal local knowledge, but attempting a global definition is going to be somewhat fruitless. Perhaps defining this even more by exclusion is the way forward.

Quick case study: UK/Oxfordshire. Here, country villages in farmland/fields are commonly served by "through" tertiary roads, but also frequently link together locally with unclassified roads. Both the tertiaries and the unclassifieds almost always paved/surfaced/sealed/tarmacadam, and lit=no, but the tertiaries are commonly lined with white paint, and are at least lanes=2. The larger ones carry reflective studs. When deciding if such a road is secondary vs. tertiary, I decide based on width and speed/density of traffic. The "unclassified" links are typically unlined, carry no reflective studs, and have a wide distribution of surface quality and general maintenance level, but nominally sealed. They may be rather narrow, with passing places. Any road in the countryside here that is unsurfaced or surfaced only in water-bound Macadam is likely to be private, belonging to a farm. So the importance hierarchy is roughly reflected in the physical characteristics, but I fully admit that *both* reflect what is quite a densely populated and prosperous part of the country.

Edited again to purge any contradictions; let's try to be clearer about the fact that the classification into OSM tags should be done by local comparison and knowledge and consideration of the road network where you are. The complex flowchart :) should have the same shape in all countries, even if the questions asked differ between countries. In the case of highway=unclassified, best if we get to it after having answered "no" to all the classifying-questions at the top of the flowchart: definition by exclusion in other words. I'm happy to integrate that notion more explicitly, since we already hint at it heavily in the leading sentence and the ValueDescription.

Willi2006: I hope my work can be deleted! This is a wiki, and it's perfectly reasonable to change or revert anything you don't agree with (but: let's not go back to the previous mess ☺).

Suggestions about specific stuff welcome, of course :) Or just go ahead and fix it.

--achadwick 21:37, 18 December 2011 (UTC)

  • Alv wrote "... based on a comparison of the road in question with other roads nearby, based on both the network, the signage and the physical form."
As pointed out already: Network yes, physical form no in global scope.
  • achadwick wrote: "The proposal/voting process should be considered broken, although sometimes the discussions are worthwhile."
Why broken? Because some people don't care about the process anymore? Because it's extra work to go through it? Because some people don't care about the rampant Wiki anymore? Even if only few people participate in discussion and vote there's a chance that a local view turns out to be inappropriate in a global scope.
  • achadwick wrote: "Do you think this tag is worthwhile or not?"
I used and I'm using this tag. I'm opposing using physical characteristics as definition or description in a global scope.
  • achadwick wrote: "... but attempting a global definition is going to be somewhat fruitless. ... Quick case study: UK/Oxfordshire. ... "
I fully agree that it's fruitless, I think even impossible to come up with global definitions. If your definitions are valid for Oxfordshire how about marking them as such as I requested in August. No objection anymore.
One example doesn't proof that definitions are valid globally but one example is sufficient to proof that they aren't valid globally. And I know more than one. I used to live in a part of Germany where most of the (public) tracks are paved (surface=asphalt, smoothness=good or even excellent). Now I'm living in a country where tracks aren't restricted to agriculture traffic and only few of them are paved. Even tertiary roads are partially or completely unpaved. The same tertiary road is small in the countryside but a dual carriage way with 2 lanes for each direction in the next town. A primary road leading from the capital to a neighbour country starts as dual carriage way but has physical characteristics of an unclassified road in the montains.
  • achadwick wrote: "let's not go back to the previous mess"
I think the mess started with mixing physical characteristics with importance for the grid.
  • achadwick wrote: "Suggestions about specific stuff welcome, of course :) Or just go ahead and fix it."
As I regard the current content as pointless it doesn't make sense to change details. For me the current definitions which I quoted in my previous contribution are fully sufficient in a global scope. For regions or countries there could and should be more precise definitions e.g. the one I made for Thailand based on and in agreement with the then global definitions. I think the best fix for the current page is to delete it. And I'm afraid I won't be able to resist to do that when the InfoBox I added is deleted again.

Willi2006 15:05, 19 December 2011 (UTC)

I don't see the OSM wiki as authoritative, merely descriptive. The OSM DB as a whole is authoritative in a rather vague global sense, and local usage in the context of the real world is authoritative too (and often more relevant). The wiki is at its best when it describes real usage in the DB and evolved consensus; proposals and voting procedures are too frequently castles in the air built by people with too little real-world knowledge and voted on by others in the same camp.

For Tag:highway=unclassified#Description and that section alone, I think there are no contradictions with Key:highway, though I'll grant you that "Unclassified roads are considered usable by motor cars" might be a bit of a stretch. Willi2006: can we agree on that section, please?

The remaining sections are more contentious, but for high-quality documentation I think we need a section offering hints about how to use this tag. To move forward, would it make sense to move that here and fix it up collaboratively? Pull the disputed bits into a new section on the talk page and thrash them around until they have a better global perspective and the best wording possible.

IMO, there's scope for offering examples of concise local physical comparisons still, provided they aren't to be taken as globally applicable. I agree with Willi2006 and Alv there. Would clarifying that further and splitting it into specific regional examples as Willi2006 suggests meet with everyone's approval? I must raid that Countryside page for the remote bits of Germany, no doubt there are remote parts of the UK it's a reasonable yardstick for. Willi2006: would you be willing to add SE Asia examples? Goal would be to offer examples of the criteria people are using to exclude other kinds of highway=* and settle on highway=unclassified in different places, and I certainly wouldn't mind replacing the rather prescriptive language we currently have with that.

--achadwick 20:45, 19 December 2011 (UTC)

I don't object to the content of section Tag:highway=unclassified#Description. However I see it duplicates content which can be found on other pages like Key:highway and Highways. I think the tag "highway=unclassified" can only be described or defined meaningful in the context with other highway tags. This is done already on the page Highway tag usage. And a comparision between countries is available too: Highway:International_equivalence. Germany, UK and Finland are already there. Thailand has it on its country page. An extract can be easily included. Thus I don't see any value in the page Tag:highway=unclassified. Any effort should improve existing pages which I regard as good already, and not in establishing new pages. Neither for authors nor for readers duplicating and distributing content on many pages is helpful.

Willi2006 05:57, 20 December 2011 (UTC)

There has been enough discussion in this thread now, and it is becoming overburdened. I consider recent changes to have resolved the issue. Your most recent objection infobox on the main page, which I have removed and which I am reproducing here, was:


This page is in contradiction to Key:highway because physical characteristics instead of "importance of the highway for the road grid" is used as criteria. Don't get confused. See discussion.

The page has been revised so that this objection no longer stands. I don't know what more we can do to keep you happy. Additionally, other users have been also questioning the objection, so I have removed the infobox. The page currently defines the tag solely in terms of the classification's position in the road hierarchy. You have been misunderstanding the purpose of the "physical criteria" that remain; they are examples of how one might determine relative importance using one's local knowledge of an area. Recent objections in this thread have been about other things, and you yourself had no objection to the revised description section. If you have further concrete objections, please raise them as further topics for discussion under specific headings and I'll try to address them sensibly. Please do not reinstate this outdated infobox verbatim and without discussion or comment again, as you did in revision 745437.

--achadwick 14:09, 4 May 2012 (BST)