Divers at the wreck of the 18th century Swedish ship of the line Kronprins Gustaf Adolf in the Gulf of Finland. The picture was taken at the Finnish Maritime History Museum, which allowed free photography.
<a href="//commons.wikimedia.org/w/index.php?title=User:Milit%C3%A4rhistorikern&amp;action=edit&amp;redlink=1" class="new" title="User:Militärhistorikern (page does not exist)">Militärhistorikern</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>