A picture of a nautical chart of Blekinge archipelago in southern Sweden – a historically important military naval base – piqued the curiosity of many after it was sent to the Blekinge Maritime Museum this month.
The chart was written in Russian and dated to the year 1980, a year before Soviet submarine U137 sparked the high-profile diplomatic incident 'Whiskey on the rocks' after it ran aground in the same area.
The mysterious map first left experts scratching their heads, but with the help of maritime history shop Fartygsmagasinet in Stockholm, where the map was found, its background has now been established.
It turns out it came from another Soviet Whiskey-class submarine which was built in 1956 and scrapped in Finland in the 1980s. At the time of its creation much of the Blekinge archipelago was a designated protected area by the Swedish Armed Forces and very much off limits to foreign vessels.
"The chart covers the Karlshamn coastline and is very detailed. You can see exact depth markings, accurate reproduction of the archipelago, approach channels, lighthouses and landmarks. Everything needed to navigate with great precision," Anders Lundquist, chairman of Blekinge Maritime Museum, told regional newspaper Kvällsposten.
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Another picture of the nautical chart. Photo: Blekinge Maritime Museum
During the Cold War the Swedish Navy repeatedly chased suspected Russian submarines along its coast.
The 1981 Whiskey on the rocks incident sparked a diplomatic standoff and certain long-lasting Swedish uneasiness when it comes to Russian subs – most notably demonstrated in Sweden's 2014 submarine hunt in the Stockholm archipelago which hit global headlines at the time.
Karlshamn has also made national headlines lately after it voiced an interest in leasing its port to aid the construction of planned Russian gas pipeline project Nord Stream 2.