Sacred Haven of Debauchery

Before surrendering Viipuri, the Soviet military mined the city with radio-controlled hidden mines, which were intended to be detonated gradually over several months, after the Finns occupied the city and settled in. The mines were supposed to be activated remotely by a radio signal at a certain frequency.

The mines were located in different parts of the city. Several mines were detonated. After some time, Finnish sappers discovered several more undetonated mines and were able to study them, thanks to the capture of several Soviet prisoners of war, who, during interrogations, told the Finns the locations of the minefields. To jam the radio signal for detonation, the Finnish sappers launched a mobile radio station, which continuously broadcast fast music over a wide range of frequencies for two months (until the batteries in the radio-controlled explosive devices were completely discharged), so that the detonation radio signal could not reach the mines. The Säkkiärvi polka was used as background jamming, which Finnish engineers chose because of the fast rhythm of the music.

As informational cover for the demining operation, Finnish propaganda spread the rumor that a radio station was turned on between the Finnish and Soviet front lines, which was under continuous fire from the enemy, so it could not be turned off.

The demining was successful, and many buildings in Viipuri survived the war.