@Loremo has set up the wiki page for the Swiss municipality mergers - v2026 for the changes that go in to effect on the 1st, thanks!
As we’ve seen over the last couple of years the number of changes is a lot smaller than it used to be, so we don’t really need a large organised effort (just the “organised” bit :-)) this year.
The notable change this year is Moutier changing the canton, and I suspect @Loremo wants to do the honours for that.
Edit: fixed link.
I added https://wiki.openstreetmap.org/wiki/Key:swisstopo:BFS_NUMMER and a few similar ones. Can it be linked from the relations?
This is possible, but seems to be a manual process: https://community.openstreetmap.org/t/how-to-link-a-tag-from-osm-org-to-its-wiki-page/7324
The tags are just an artifact from the original import and the only one we actually use is the BFS municipality id, and even for that tag the key is an obvious misnomer. It isn’t an id assigned by swisstopo it is, as already said, the municipality id of the federal office for statistics.
From my POV we could delete all of the historic tags with the exception of the BFS id.
Thanks for the link to github. Eventually, it would be good to request an update. I noticed the value links are updated once per month.
Ideally they would have different names (like “ref:CH:BFS:MUNI_NB”), but “swisstopo:BFS_NUMMER” is mentioned several times in the wiki and possibly elsewhere.
swisstopo:KANTONSNUM could be limited to cantons, swisstopo:BEZIRKSNUM to districts .. swisstopo:SHN needs a bit more info.
I asked for an update at Talk:Wiki - OpenStreetMap Wiki
Can we restore this relation: Relation: Ménières (1683371) | OpenStreetMap ?
Keeping it with the historic boundary seems consistent with the outline on mergers mentioned above. There are no other admin boundary elements with the same name.
More general question: is it customary to include the village or locality of the same name as “admin_centre”? I noticed it being done at some places, but not always. Personally I find it useful, especially when the municipality isn’t exactly centered.
Also, I noticed some municipalities using “addr:postcode”, other “postal_code”. Should this be included or not? If yes, with one value, several or all values? Maybe “addr:postcode” is useful if there is one (but I guess that can change). In general, I’m not really convinced by this.
I’d complete the relations on municipalities at least with their website.
It’s essentially never useful, PLZ6 boundaries (there are nearly 6’000 of them) as a rule do not match municipality boundaries.
The cases in which it is IMHO mandatory: municipality name does not match the name of the admin_centre and/or municipality name has a disambiguation but that is not locally in use for the admin_centre. Even if it wouldn’t be necessary it doesn’t do any harm, particularly if there are multiple inhabited places inside the municipality.
I had in mind places like Relation: Vernier (1685540) | OpenStreetMap pointing to Node: Vernier (36650976) | OpenStreetMap
Relation: Carouge (1685459) | OpenStreetMap and Node: Carouge (240046137) | OpenStreetMap
Obviously, the actual admin may be located there or not.
Maybe this is some left-over from OpenGeoDB.
Sample: at Node: Le Grand-Saconnex (36650978) | OpenStreetMap where openGeoDB:community_identification_number remains.
This is now active.