[OSM-dev] determining the boundaries of cities?

[Paul Norman]

> From: Ákos Maróy [mailto:akos at maroy.hu]
> Subject: [OSM-dev] determining the boundaries of cities?
> 
> Hi,
> 
> I wonder what is the best way to determine city boundaries based on the
> OSM dataset. What I want to do is simply to have each city colored in
> light yellow (uniformly), with a black outline at the edge of each city.w
> I'm not concerned about the streets inside the cities, etc.
> 
> I looked at the OSM data for Hungary, and of course at the OSM Wiki, but
> I'm still yet to be able to determine the best way to achieve the above.
> 
> One possibility seemed to be to go with:
> 
> boundary = administrative && admin_level = 8
> 
> 
> but this will actually create a full tiling of the map - the edges of
> these areas not the edges of the cities themselves, but they 'fill up
> the space' up to the neighboring such areas. basically the 'rural area'
> between the cities is filled up

In many places this is correct. Frequently there is no land between cities -
all the land is in a city. For example, in Greater Vancouver all the land
belongs to one city or another, including the farmland.

I can't answer definitively for Hungary, but it sounds like that's the case.