Limestone rock with a beautiful one in the middle <a href="https://en.wikipedia.org/wiki/Breccia" class="extiw" title="en:Breccia">breccia</a> (limestone pieces sticked together). The grooves in the rock were created by limestone solution. This phenomenon is called "karst". The grooves are called <a href="https://en.wikipedia.org/wiki/Limestone_pavement" class="extiw" title="en:Limestone pavement"> karst</a> and is a rare habitat.
<a href="//commons.wikimedia.org/wiki/User:Agnes_Monkelbaan" title="User:Agnes Monkelbaan">Agnes Monkelbaan</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>