I want to start a discussion about the “proper” OSM admin level for Dutch cities. I think it would be better of it was changed (if even possible), but that’s just one person’s opinion. I’m curious to hear what others think.
Since the big data update Dutch cities are equivalent to admin level 8, which correspond to municipalities (“gemeentes”) in real life. For big(ger) cities this is not an issue, as they are contained in their own municipality, and it is all the same. For smaller cities in the countryside, often several towns form one council together, and this is what is used by Citystrides. Example from near where I live: Gooise Meren is used, which contains Muiden, Muiderberg, Naarden and Bussum. These used to be in Citystrides as separate cities. Those correspond to admin level 10.
So I think level 10 should be used, mainly for 2 reasons:
that is the level that most people recognise cities at, and have an emotional attachment to
they are easier to complete
However it is not without consequences. I have seen for instance that Amsterdam has 2 children at level 10: Amsterdam and Westpoort (an industrial area). I have no clue what merits Westpoort admin level.
So my question: do you agree or disagree that Dutch cities should be at level 10? If you agree, can you see anything that could go wrong in the area that you know well? Drilling down from here (Nominatim Demo) on the Administrative section will get you to the appropriate levels.
I think that the current level (8), based on municipalities, is better. Boundaries of municipalities are unequivocal and well-defined, they cover 100% of the territory. Level 10 borders are poorly defined (they are usually historically justified, but not always precisely, as borders shift or open data contributors are just ignorant) and level 10 includes both artificial splits like the one you noticed in Amsterdam (reflecting ad hoc decisions of a random open map editor, not any historical reason), and it may also include too small units with 1-2 streets.
Borders of municipalities are well defined, and what is a street is defined/decided (and how it is named) by the municipality (not a town within it).
The only reason I might see for such a lower-level split is if there are a lot of streets with the same name, in the same municipality, but in a different town. In Belgium and in Germany which also have the split based on municipalities consisting often of several towns this is rare, and for those cities which I did run in the Netherlands, it has not yet happened to me.
The problem with too small units is clear for example in Poland, where the imported data sometimes is based on village-level units, and extremely inconsistent, while municipality-level units would provide a more consistent approach - but that’s for a different post. For the European Union countries I think the rule of thumb should be to use the unit corresponding to the LAU (local administrative unit) in the statistical/administrative system, which provides for a very clear and relatively consistent approach.
I don’t think level 10 is going to work. An example i looked up in osm is for instance the 1 year old city of Beekdaelen. This is now level 8 and the old towns: Schinnen/Nuth/Onderbanken are now changed to level 10. These 3 are nicely visible.
BUT
Some years ago city Landgraaf was made out of Schaesberg/Nieuwenhagen/Ubach over Worms.
And looking up one of those 3 doesn’t give me a administrative level 10 at all!
so going for level 10 would give quite some inconsistencies, and although i like seeing more cities completed (in 2019 Beekdaelen was created, and my 3 completed towns were merged automatically to 1 ), i guess level 8 is the way to go.
Note that this was in no way meant as a criticism of your excellent work. I checked the admin level sheet myself for The Netherlands, I didn’t realize what the effects would be for smaller towns, until I saw it in action.
Out of curiosity: when there is a new data update from OSM, will the current cities stay the same, or will you import the cities again according to the admin level at that time?
Example: the town of Weesp is set to join the municipality of Amsterdam (probably in 2022). If that make it to OSM, will that eventually mean Weesp is no longer in Citystrides?
Oh I didn’t mean it to come across like I felt criticized - it’s all good. (I welcome criticism though - I’m not perfect and realize there are pieces of CityStrides that are absolute trash )
I haven’t built the data update part of the global data, but that is the plan.
), i guess level 8 is the way to go.
)