[Tagging] Classifying roads from Trunk to Tertiary and Unclassified

Joseph Eisenberg joseph.eisenberg at gmail.com
Mon Aug 12 16:02:44 UTC 2019


My initial question was really about Indonesia in particular, and
countries without established, official highway classification systems
in general.

But I took a look at Spain, and while I don't know much about the
local road system, the use of highway=trunk vs highway=primary looks
quite good!

See the current rendering around the city of Soria, Spain:

There is 1, and only 1, trunk road (or motorway) from Soria to each of
the 7 cities around it.

This is also true of Cordoba:

And it looks like every place=city in Spain is connected by
highway=trunk or highway=motorway to all of the other cities. This
means you can render a map with just these 2 tags and place=city, and
have a complete national roadmap.

I actually think this is a great example of what I would like to see
in Indonesia.

In contrast, look at Toulouse, France:
- A highway peters out to the northeast (toward Lyon) and to the south
(toward Andorra). But if you zoom in to see the primary roads, it's
clear that the highway has switched from trunk to primary mid-route.
This makes it difficult to render a proper map.

Nancy, France is similar: https://www.openstreetmap.org/#map=7/48.655/6.141
There are several roads that have trunk segments, but come and go (eg
towards Paris, Rheims, Strasbourg, and Mulhouse). It looks like
missing data or a rendering error.

I imagine that mappers in France are using "trunk" for certain
features, like a dual carriageway (2 lanes in each direction, divided
by a barrier), or "expressway" or "motorroad" features, but since
these are only used in certain places, the road looks like it comes
and goes. This means that you have to render highway=primary at all
zoom levels, or else the road network is incomplete.

In theory, private map renders can edit the data to make a nicer
picture, but automated renderings based fully on OSM data (like the
standard layer on openstreetmap.org - Openstreetmap-carto) will not be
able to do much with the situation in France, especially when you look
at how many primary highways there are in a place like England -
rendering those at z5 to z7 leads to quite a mess:


On 8/12/19, yo paseopor <yopaseopor at gmail.com> wrote:
> In Spain we have big problems, discussions and arguments with that
> question. Last month, a French user complained about the state of a
> "Nacional" (Country Main Road) classified in OSM as trunk.
> These problems have one main reason. Here in Spain, in some places, there
> are six degrees of public administration: European Union, Estado (Country),
> Comunidades Autónomas (state), Provincia (province), Comarca (like county),
> Municipio (like town)...and fourth of them have competences and decisions
> about that.
> Also some Comunidades Autónomas make better investments and spend more
> money in some zones than Country government (because Country government
> prefers to do only motorways all over Spain) . But as for more people
> Country government is the most important (or the only important government
> for the country) the majority of roads that depends of that government are
> "defacto" the most important: trunk.
> This is a mess and a disaster because you have some trunk roads
> (nacionales) that don't deserve this category: roads with less width than
> normal for two lanes,level crossings for all kind of tracks, passing-by
> little villages,  horrible smoothness and with the same track as they were
> created sixty or seventy years ago. Also you have good new 21st century
> ways with only interlevel crossing, average speed of 80/100, big widths per
> lane, but as they are from the government of the province ("Diputaciones")
> or from the government of the "state" they are automatically primary ,
> secondary or tertiary roads. This is not fair. Think about it: a government
> will not spend its money in a road that is not really important.
> Barcelona's Province Government manages about one thousand million euros
> budget. So I assure you if  Barcelona's Province Government wants to build
> a new road in a well-populated area this road would be as good as primary
> or trunk.
> Some people in OSM Spain want other classification criteria (not
> administrative but physical) to make more objective the road
> classification:
> trunk: 4,3,2-lane new roads (newer than twenty years, with new track), with
> only interlevel crossings and exits, average speed of 80/100, and wide
> lanes. It is possible bikes or agricultural vehicles would be prohibited in
> these kind of ways.
> primary: 3,2-lane main roads, with crossings at the same level, average
> speed of 60/80, and wide lanes. All traffic should be allowed.
> secondary: 3,2-lane roads, connecting small territories, crossings at the
> same level, always with road marks , average speed of 50/60, acceptable
> width per lane.
> tertiary : 2-1-lane roads, with reference, it is not necessary to have road
> marks, average speed of minus than 50, it is not necessary to have the
> width of 2cars.
> We want also to use governments data like average speed and average daily
> traffic (ADT) . Objective data should be consulted to take these decisions.
> We want to take consideration of all "Country government roads" that have
> big motorways near to make lower they category. In the reference we will
> always have the administrative classification like N- Country C- State
> L-Local and others like CV-V for the town. One road can be trunk at first
> kilometers with good track, etc. and then when sharing track with the free
> motorway can be tertiary.
> We also aware Spain is not the same as Australia or Africa , we know
> classification criteria cannot be the same due to physical conditions in
> other countries. But some of them we want a real and objective ,
> non-repetitive classification criteria (using letters of the reference and
> the same classification in OSM is the same, talking administratively) for
> tagging Spanish Roads in Openstreetmap.
> Salut i carreteres (Health and roads)
> yopaseopor
> On Sun, Aug 11, 2019 at 11:37 PM Paul Allen <pla16021 at gmail.com> wrote:
>> On Sun, 11 Aug 2019 at 22:10, Graeme Fitzpatrick <graemefitz1 at gmail.com>
>> wrote:
>>> In Australia, it's not uncommon for a Primary (& in some cases, Trunk!)
>>> road to be a single lane dirt road!, & it would be nice to be able to
>>> show
>>> them with the importance that they are to local residents of that area.
>> There appear to be two schools of thought on this.  One is that if it is
>> the only road between A
>> and B then it is a primary road, even if it's a single-lane dirt track.
>> The other is to adopt
>> a consistent country (or state, or region) wide classification,
>> preferably
>> adhering to official
>> classification if there is any, which might mean that the only road
>> between A and B is a
>> secondary, tertiary or even quaternary road.
>> I favour the latter approach.  If there is only one single-lane track
>> between A and B then
>> it is obviously of importance to those in the area without it needing to
>> be emphasised by
>> a different colour.  Whereas rendering it as a primary road will mislead
>> some people
>> planning a cross-country trip into think it's paved highway all the way,
>> including the
>> final part of their trip from A to B.
>> I suggest that before you decide which approach best suits your country
>> you first check
>> if there is a governmental classification scheme of highways.  It appears
>> that, for Australia,
>> things are rather inconsistent across the states and territories and have
>> changed over
>> the years.  Nevertheless, alphanumeric designations are now common
>> amongst
>> most
>> states and territories and the meaning of those designations can be found
>> at
>> https://en.wikipedia.org/wiki/Highways_in_Australia#Prefix_letters
>> After examining that, then make your decision as to whether or not the
>> OSM
>> map ought
>> to reflect official designations or do its own thing.  And then discuss
>> it
>> in whatever forum
>> Australian mappers use and see if you can get a consensus agreeing with
>> you.
>> --
>> Paul
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