I'm sorry to have needed to undo your edit to Zwiefalten. There are always problems about finding equivalent terms for layers of local government in other countries. You're right: "bwrdeistref" means "borough", but it is also used to mean "municipality" (see "Geiriadur yr Academi" for example). And I'm not convinced that "comuned" is any better. It's clear that a lot of work needs to be done on places in Germany, so I think it's better not to rush into any quick solutions. If you know any reliable sources in the Welsh language that discuss these layers of German government, that would be helpful. --Craigysgafn (sgwrs) 13:13, 3 Awst 2020 (UTC)Ateb

Not worries, I see what you mean: Borough as in Categori:Bwrdeistrefi'r Unol Daleithiau, which translates to the German "Stadtbezirk", which also means both "borough" and "municipality", at least in the case of the USA. I fixed Categori:Bwrdeistrefi'r Almaen‎ and Categori:Bwrdeistrefi yn ôl gwlad to correspond on Wikidata with the German "Stadtbezirk" and not the Dutch "Stadsdeel" ("Stadtteil" in German) with only ever refers to borough, never to municipality. Cycn (sgwrs) 13:37, 3 Awst 2020 (UTC)Ateb
@Craigysgafn: Categori:Bwrdeistrefi'r Almaen‎ now has a lot more interwikis, including some that might be more obvious to you. They are all attempts to translate the German concept "Stadtbezirk", buy do these correspond with the Welsh concept of "bwrdeistref" (enough for the German case, at least)? Cycn (sgwrs) 13:40, 3 Awst 2020 (UTC)Ateb