Cologne: Cologne Cathedral (officially: <i>Hohe Domkirche St. Peter und Maria</i>), center of the clerestory of the choir with some of the in all 48 <i>Koenigsfenster</i> (King Windows) created around 1300
<a href="//commons.wikimedia.org/wiki/User:Mylius" title="User:Mylius">Mylius</a>
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<span class="int-own-work" lang="en">Own work</span>