def METHOD_NAME(self):
    """traverses the pages for different waste types and collects download links for the iCals"""
    if self._region is None:
        self._region = self.determine_region()
    # create waste type urls
    ical_urls = []
    urls = [urljoin(URL, u) for u in WASTE_TYPE_URLS.get(self._region)]
    for u in urls:
        r = requests.get(url=u, headers=self._headers, cookies=self._cookies)
        soup = BeautifulSoup(r.content, "html.parser")
        download_link = soup.findAll(
            "a",
            {
                "class": "piwik_download_tracker",
                "data-trackingtyp": "iCal/Kalender",
            },
        )
        if len(download_link):
            ical_urls.append(urljoin(URL, download_link[0].get("href")))
    return ical_urls