The wire pull line (double wire line) of a <a href="https://en.wikipedia.org/wiki/Railway_semaphore_signal#Operation" class="extiw" title="en:Railway semaphore signal">mechanical railway semaphore</a> on the <a href="https://en.wikipedia.org/wiki/Brunswick%E2%80%93Uelzen_railway" class="extiw" title="en:Brunswick–Uelzen railway">Braunschweig – Wieren railway line</a> is piped under a track.
<a href="//commons.wikimedia.org/wiki/User:TeWeBs" title="User:TeWeBs">TeWeBs</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>