walpurgis night ("valborgsmässoafton" in swedish, "vappu" in finnish, "volbriöö" in estonian, "valpurģu nakts" or "valpurģi" in latvian, "walpurgisnacht" in german), "čarodějnice" in czech is a holiday celebrated on april 30 or may 1, in finland, sweden, bohemia (czech republic), estonia, latvia and germany.