<p>Russian <b>152 mm/35 gun M1877</b> gun (152мм/35 орудие обр. 1877 г.), displayed in Suomenlinna fortress, Helsinki.  This gun was initially mounted on warships (most likely the <a href="https://en.wikipedia.org/wiki/Imperator_Aleksandr_II_class_battleship" class="extiw" title="w:Imperator Aleksandr II class battleship">Imperator Aleksandr II class</a>), then placed in role of coastal artillery. <a rel="nofollow" class="external autonumber" href="http://flot.parus.ru/arms0038.htm">[1]</a> <a rel="nofollow" class="external autonumber" href="http://www.navweaps.com/Weapons/WNRussian_6-35_m1877.htm">[2]</a>
The stamp on the breech indicates the gun was produced in 1889.
Photo taken on June 10, <a href="//commons.wikimedia.org/wiki/2006" title="2006">2006</a>.
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Source: Photo by me, <a href="//commons.wikimedia.org/w/index.php?title=User:Balcer&amp;action=edit&amp;redlink=1" class="new" title="User:Balcer (page does not exist)">User:Balcer</a>.
<a href="//commons.wikimedia.org/wiki/User:Balcer~commonswiki" title="User:Balcer~commonswiki">Balcer~commonswiki</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>