JOSM is much more suitable for editing relations.

It has the nice you can easily create multipolygons by selection the outer and inner ways and using the 'Create multipolygon' function, or use the 'Update multipolygon' feature to move the appropriate tags from the outer way to the existing relation.

https://josm.openstreetmap.de/wiki/Help/Action/CreateMultipolygon

The wiki has the reference documentation for multipolygon relations:

osm.wiki/Relation:multipolygon

The tags describing the feature need to be on the relation instead of on the outer way.

The wiki documents multipolygon relations. Since it's a wiki it can be made to say anything you want. :-)

I'll point you to this instead: http://area.jochentopf.com/old-style-josm.html

You can keep arguing here against the deletion of relations with only type=multipolygon tags, but that won't convince any one. Tag the relations appropriately, as documented in the Multipolygon wiki for example, and the relations won't even show up in the old-style multipolygon dataset. Or if you cannot tag it like a proper multipolygon, at least document your intentions with the relation in a fixme or note tag.

I've been fixing old-style multipolygons in a variety of ways on a daily basis for over a year now, if you keep creating invalid multipolygon relations like these I will step on your toes again. If you don't want that, learn for this discussion and tag the relations appropriately.

osm.wiki/Multipolygon

As long as the tags are on the ways and not on the relation it's not a proper multipolygon.

Using a relation to group ways is okay, but using type=multipolygon for the relation is not.

Adding fixme=<some reason> to the relation will keep it out of the data set I use to fix old-style multipolygons. You should take note of that if you don't want improper multipolygon relations touched.

It is when the tags are better left on the ways, the relation has no added value.

If you don't want multipolygon relations to be touched, you need to ensure they have proper tags along with the type=multipolygon.

In this case using a different type than multipolygon is probably more appropriate even.

Then tag the multipolygons appropriately so they are not considered old-style multipolygons (with only the type=multipolygon tag on the relation).

In short: don't put tags on the outer way and have only type=multipolygon on the relation, move the tags from the outer way to the relation.

For further reading: osm.wiki/Relation:multipolygon

Yes, see version 1 of relation/8076915.

That's what it looks like on the imagery.

You're free to improve the tagging.

I'm just fixing old-style multipolygons with no tags on the relation.

Quite possibly, yes.

English is fine on the Dutch forum as well, pretty much all Dutch people speak it unlike German.

I fixed self-intersections, but user vnsnt deleted the relation with natural=wood in changeset/51524321, see:

changeset/51524321

You need to revert this changeset if you want to restore the wood.

Can you be more specific?

relation/6897261 has been deleted by another user in the mean time.

Because the metropoolregio is made up of municipalities (admin_level=8) and provinces (admin_level=4), it replaces the "plusregio" (admin_level=6).

For details of admin_levels in The Netherlands see:

boundary=administrative#11_admin_level_values_for_specific_countries

The metriopoolregio is a kind of administrative unit, but in the same way as provinces, municipalities, and cities (woonplaatsen).

Further discussion of metropoolregios should be down on the Dutch forum:

http://forum.openstreetmap.org/viewforum.php?id=12

Please stop creating old-style multipolygons (with tags on the outer way instead of on the relation), these have been deprecated quite some time ago and will no longer by osm2pgsql 4.0.0 and other OSM tools.

See: http://area.jochentopf.com/

area:highway doesn't make much sense on a MP relation which is already an area. I've made this kind of change more often while updating old-style multipolygons.

You're welcome.

Please stop creating old-style multipolygons (with tags on the outer way instead of on the relation). These are deprecated for quite some time, and osm2pgsql 4.0.0 no longer supports them, nor do recent JOSM versions render them any more.

Please update your JOSM to the latest tested snapshot (12275) which has better validator support for old-style multipolygons, to help you prevent creating any new ones from now on.

See also: http://area.jochentopf.com/

Please stop creating old-style multipolygons (with tags on the outer way instead of on the relation).

osm2pgsql 4.0.0 has dropped support for old-style multipolygons.

You also need to update your JOSM to the latest tested snapshot which (12271) which has better validation for old-style multipolygons and doesn't render them by default any more either helping you to spot these issues before uploading.