The picture shows the The centre of the <a href="https://en.wikipedia.org/wiki/Graduation_tower" class="extiw" title="en:Graduation tower">Gradieranlage</a> Maria Fieberbründl, with two benches in the middle and all around with the branches of the Gradieranlage and the catch basin for the salt water.
<a href="//commons.wikimedia.org/wiki/User:RosiLovesWiki" title="User:RosiLovesWiki">RosiLovesWiki</a>
<span class="int-own-work" lang="en">Own work</span>