An example natural monument sign as it is used in Lower Austria.
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<a href="//commons.wikimedia.org/wiki/File:Schild_Naturdenkmal_in_St._P%C3%B6lten.JPG" title="File:Schild Naturdenkmal in St. Pölten.JPG">File:Schild Naturdenkmal in St. Pölten.JPG</a>