Unable to answer "What’s the topic of this information board?" – Information Board – node/11799888537 via StreetComplete 57.1:

Infotafel

Attached photo(s):
https://westnordost.de/p/205814.jpg

Aussichtspunkt

via StreetComplete 57.1

Attached photo(s):
https://westnordost.de/p/205849.jpg

Area, not only way

via StreetComplete 52.0

Attached photo(s):
https://westnordost.de/p/143158.jpg

"Tried finding, does not exist"
The place has gone or never existed. A user of Organic Maps application has reported that the POI was visible on the map (see snapshot date below), but was not found on the ground.
OSM snapshot date: 2023-03-29T15:44:03Z
POI name: Firenze 040
POI types: amenity-post_box
#organicmaps

It is, apparently, rather a museum or so?

via StreetComplete 52.0

Attached photo(s):
https://westnordost.de/p/143187.jpg
https://westnordost.de/p/143188.jpg

Unterstand/schieshütte

via StreetComplete 57.1

Attached photo(s):
https://westnordost.de/p/205689.jpg

Inoffizielle weg?

via StreetComplete 57.1

Attached photo(s):
https://westnordost.de/p/202952.jpg

GPS Trace: @YieldMapper/traces/11311143

2x carsharing

via StreetComplete 57.1

Attached photo(s):
https://westnordost.de/p/202703.jpg

Privatparkplatz

via StreetComplete 57.1

Attached photo(s):
https://westnordost.de/p/202857.jpg

In context of overlay "Things" – Wayside Cross – node/11755428826 via StreetComplete 57.1:

Unbekannt ob doch "Kreuz ohne religiösen Wert"? Christenkreuz

Attached photo(s):
https://westnordost.de/p/202873.jpg