The Saimaa Canal. Mälkiä lock.
<a href="//commons.wikimedia.org/wiki/User:%D0%9B%D0%B5%D0%BE%D0%BD%D0%B8%D0%B4_%D0%9F%D0%BE%D1%80%D0%BE%D1%88%D0%BA%D0%BE%D0%B2" class="mw-redirect" title="User:Леонид Порошков">Леонид Порошков</a>
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<span class="int-own-work" lang="en">Own work</span>