The angular Powder Tower is one of the few surviving fragments of the city fortification. Built in 1321 as a warehouse for gunpowder and weapons, the Tower with 2m-thick walls was subsequently used for other purposes. The second name of the tower is the Jewish Tower, because wealthy Jews were kept in custody in it, and, often undeservedly. They could only be freed giving bribe. If you climb to the top of the tower, you can at once see two outstanding scenes: the panorama of Konstanz and the landscape of the Rhine.