The creation of this clock started during the 15th century and now is the oldest astronomical clock still operating. The clock master Mikuláš of Kadaň this masterpiece with the help of Jan Sindel (professor of mathematics and astronomy of Charles University). The astronomical dial displays the time, solar position, lunar phases, zodiac sign, sunset and sundown. The lower dial displays a calendar (created by Josef Mánes); the golden paintings represent the months and the outer ring mark the day, the week and feast days. Every hour on the hour the clock strikes and the little figurines next to the open dial move, they represent vanity, greed, death and vice. The apostles will parade when the upper windows open. Do not miss this display!