The watchtower – Sujumbike Tower – at Kazan Kremlin deserves special mentioning. It is also called “falling tower”. It slightly deviates aside, now the deviation of the tower spire is about 2 meters. There are no documents of tower construction left as the archive, where these documents were kept, was destroyed in 1701 during the fire in Moscow. This is the reason why argues on the age of the tower are still acute: some date its foundation to the period of Kazan Khanate.