The search history seems to have changed a little bit recently. It works better than before but is still not as intuitive as on most other navigations. Thanks, by the way, for ignoring spaces at the end of auto completed seach terms now. This helps a lot.
Admin Level 5 = https://www.openstreetmap.org/relation/72022 = Regierungsbezirk Köln (state-district border)So Cologne as city has admin level 6 and is split into Stadtbezirke (which have their own local self-government, admin level 9). These Stadtbezirke are split into Stadtteile (admin level 10). Ehrenfeld is a Stadtbezirk but "unfortunately" it contains a Stadtteil with the same name which makes it a bit confusing. Another Stadtteil within the Stadtbezirk Ehrenfeld is Bickendorf.
Admin Level 6 = https://www.openstreetmap.org/relation/62578 = Köln (county border)
Admin Level 9 = https://www.openstreetmap.org/relation/2613797 = Ehrenfeld (part of municipality 1 = Stadtbezrirk)
Admin Level 10 = https://www.openstreetmap.org/relation/2613726 = Ehrenfeld (part of municipality 2 = Stadtteil)
Admin Level 10 = https://www.openstreetmap.org/relation/2613714 = Bickendorf (part of municipality 2 = Stadtteil)
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