[OSM-dev] determining the boundaries of cities?

[Ákos Maróy]

Peter,

> In Germany the speed limit is the case by default, but in the city there
> may be different limit signs even increasing that.
> One problem with this kind of "boundary" is, that it's only defined
> along streets, not on every small way and not in between.
> One proposal to tag this is [1], referring not to the boundary, but to
> the points on the boundary where the city limit starts.

I'm aware of that, I just wanted to point out a usual way one encounters
this limit.

> In Germany this distinction is not true.
> As far as I know this kind of public infrastructure is provided in areas
> that are planned to be used for a specific purpose like building houses
> or sth. like that.

then again, this was also just an example. yet another example would be
that this is the area which is the basis of calculating a city's
population. or, people have postal addresses in the city within this
area. or, when you drive a taxi, it will take you within this area, and
will double-charge (for the return trip) beyond this area. or on a
tourist map, this area will be marked as the area of the city. or, if
you ask someone where he lives, he will mention this city if he lives
within the city limits. or, when people vote on local elections, they
will vote for the mayor & local offices for this city from within this area.

what I'm referring to is the city proper, or city limit:

http://en.wikipedia.org/wiki/City_limits

this is the area that the municipality has jurisdiction over. areas
beyond this area are handled by other agencies, e.g. the county, etc.

> landuse=residential should match areas mainly used for residenting -
> houses to live in.

unfortunately it does not :( for example, most of the city of Budapest
is not covered with any sort of landuse marking. OTOH, most smaller
cities within Hungary are.

> parts of cities clearly are at least:
> landuse=commercial
> landuse=cemetery
> landuse=brownfield
> landuse=construction
> landuse=garages
> landuse=greenfield
> landuse=industrial
> landuse=railway
> landuse=retail
> landuse=village_green
> 
> but not the other way around, e.g.:
> there may be landuse=construction that does not belong to cities.
> there may be landuse=railway outside of cities

thanks, I did start down on this approach, but as said earlier, it's
actually not conclusive.

OTOH, I wonder what boundary = administrative && admin_level = 8 is
marking on the Hungarian map? it is marking areas which are clearly
beyond city limits. if one would follow this marking, one would conclude
that actually there are only urban areas in Hungary, and no rural areas
- nothing would be 'outside of cities' - which is clearly not the case.

> I don't think we have something like that, as - see above - the big
> question here remains: what is an urban area and what is a rural one?

see above: the city proper, where the city municipality has
jurisdiction. IMHO this is a clearly defined legal category.


Akos