The Solovki Stone was a reminder that the USSR's first permanent concentration camp was set up in 1923 when Lenin was leader of Soviet Russia. In Solzhenitsyn's vivid analogy, the Solovki prison camp was the cell from which the entire Gulag evolved. In time the Stone on Lubyanka Square became the focus of remembrance in Moscow. The idea was copied more than once, in St Petersburg, for instance, when it erected a similar memorial in 2004. The original impulse came from northwest Russia.