Foto: "<a href="https://ccnull.de/foto/aerial-drone-photo-of-adenauer-weiher-with-cologne-bundesliga-stadium-rheinenergiestadion-in-the-background/1045240" target="_blank">Aerial Drone Photo of Adenauer Weiher with Cologne Bundesliga Stadium RheinEnergieStadion in the Background</a>" von <a href="https://ccnull.de/fotograf/marco-verch" target="_blank">Marco Verch</a> via <a href="https://ccnull.de" target="_blank">ccnull.de</a> - <a href="https://www.flickr.com/photos/160866001@N07/49858029481/" target="_blank">Bildquelle</a>, <a href="https://creativecommons.org/licenses/by/2.0/de/" target="_blank">CC-BY 2.0</a>