The Großer Reinerteich, also called Großer Annateich. The biggest and westernmost of the Reinerteiche in Gratwein-Straßengel, Styria
<a href="//commons.wikimedia.org/wiki/User:Liuthalas" title="User:Liuthalas">Liuthalas</a>
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<span class="int-own-work" lang="en">Own work</span>