Karls grav is a Swedish canal that helps connect lake Vänern with Kattegatt. It was built on the orders of Karl IX (Charles IX) and "Karls grav" means "Karl's grave", due to the number of persons who died working on the canal.
Johan Jönsson (<a href="//commons.wikimedia.org/wiki/User:Julle" title="User:Julle">Julle</a>)
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>