[OSM-talk] administrative boundaries and is_in

[Tony Bowden]

Robin Paulson wrote:
>> Do you mean that a commune (the lowest level of self government) can
>> be part of more than one unit of each of higher levels? Like this?
> yes. some examples:
> i think turkey lies partly in europe, partly in asia?

There are other examples at even this high a level as well.

Parts of France are in South America (lots of people are surprised to 
find that Brazil has a land border with the EU). Parts of Spain are in 
Africa (Melilla, Ceuta, etc).

And there lots of towns or cities that are in different geographic 
countries than administrative ones (Campione and Büsingen are Italian 
and German towns in Switzerland, Llívia a Spanish town in France, etc)

Usually these are enclaves or exclaves, so slightly easier to deal with, 
but we need to constantly remember that the world is a very tricky thing 
to model, with large numbers of quirky edge cases.

Tony