St Olaf’s Church, Tallinn

St Mary's Cathedral, Tallinn

Tallinn, Estonia

St Olaf’s Church In Tallinn is thought to be from the 12th century, though the exact date is unknown. Its first written mention was  in 1267. Interestingly, it is thought that at one time, between 1549-1625, this was the tallest building in the world. More interestingly, during the Soviet Union the tower was used by the KGB for surveillance.

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