Page not found (404)

Request Method: GET
Request URL: https://www.markt-20.de/veranstaltungen/archiv.html/
Raised by: project.views.EventDetail

Konnte keine Veranstaltung mit diesen Parametern finden.

You're seeing this error because you have DEBUG = True in your Django settings file. Change that to False, and Django will display a standard 404 page.