Festung Konigsberg - Fortified Postion "Poterna"

ul. Litovskiy Val, 21А, Kaliningrad
Kaliningradskaja oblast, Russia

This underground fortification was built between 1843 and 1860 and saw heavy fighting in the Battle of Konigsberg in 1945.

Relevant info:

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Text by: Kaj Metz

Photo(s): Cees van Esch