Now fully renovated, this tower/museum is an excellent introduction to the history of Tallinn's defences. Built 1475 - 1481, the 45m, six-storey cannon tower played a key role in the Livonian War and still has nine of Ivan IV's cannonballs embedded in its walls. The top floor houses a café with some excellent views. And where did the tower get its name? Check out the voyeur's view from the windows for yourself as you climb upward.

Admission 70kr. Joint ticket with the Bastion Tunnels 130kr.