IIRC one of the prerequisites to take part with this system is the possession of a passport which holds biometric information on a RFID tag such as fingerprints or facial information or even both.
Then the process on the immigration just verifies...
Well, it was some years ago when I twice took part on the walkaround with German language „Pilgerseelsorge“. I think an important difference to the francophone pendant was/is that they don’t take donations and don’t even ask for.
As far as I know...
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