The imperial government in St Petersburg used it in the 19th century to exile their opponents while in the 20th century the communist government by then in Moscow used the area for the worlds largestever chain of prison camps called the Gulag

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The imperial government in St Petersburg used it in the 19th century to exile their opponents, while in the 20th century the communist government, by then in Moscow, used the area for the world's largest-ever chain of prison camps called the Gulag.