<a href="https://en.wikipedia.org/wiki/en:Cathodic_protection" class="extiw" title="w:en:Cathodic protection">Cathodic protection</a> markers, for a gas pipeline. France
<a href="//commons.wikimedia.org/w/index.php?title=User:Pyrog&amp;action=edit&amp;redlink=1" class="new" title="User:Pyrog (page does not exist)">Pyrog</a>
<span class="int-own-work" lang="en">Own work</span>