The sources of the Vorderen Rettenbach are on the edge of the Kalkalpen National Park in Upper Austria. It has a length of approx. 4 km and flows in a wide funnel into the Klaus reservoir .
<a href="//commons.wikimedia.org/wiki/User:Isiwal" title="User:Isiwal">Isiwal</a>
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<span class="int-own-work" lang="en">Own work</span>