Hi Simon
anybody have a good suggestion for tagging this?
I was not aware of "Bergpoststrassen" before... :-)
Wikipedia quotes this as source:
https://web.archive.org/web/20130530130617/http://www.postauto.ch/pag-starts...
It has an english translation here:
https://web.archive.org/web/20130621160832/http://www.postauto.ch/en/pag-sta...
"Bergpoststrassen" was translated to - mountain routes - mountainous postal routes
Maybe you would like to use these as a starting point for creating a tag?
Best regards
Lukas