The fact that it‘s the oldest astronomical clock working combined with the high complexity makes it a magnificent attraction.
Every round hour there is a play where the figures of the clock start moving. You should definitely be there at least once and take a look.
The story of the maker is also very interesting. In order To prevent him building such a masterpiece in another city he was blinded and his tongue was cut. At the end he committed a suicide by jumping from the tower above the clock.