2 hours drive from Vienna. The clock tower was first mentioned in the 13th century. During the re-fortification of the Schlossberg from the middle of the 16th century, the tower received its current appearance. The hands on the mighty clock faces often cause confusion. Do the clocks run differently in Graz? No. The fact that there were originally only large hands for the hours that were visible from afar and those for the minutes were only added later resulted in the hands being mixed up. The clock mechanism still works today, but has been electrically operated since the middle of the 20th century. When there were fires in the city, the fire station on the clock tower rang the fire bell. The oldest bell in Graz, cast in 1382, strikes the hours. The "poor sinner's bell" (around 1450) was rung during executions and later warned night owls, which also earned it the nickname "rag bell". At three corners of the tower there are coats of arms that once adorned the fortifications of the castle hill.