Astronomical Clock

The  clock was built by Hanus, a master clockmaker, in 1490. The town councillors were so anxious to prevent him from recreating his masterpiece elsewhere that they blinded him.

The Earth was the centre of the universe. The purpose of the clock was not to tell us the exact time but to imitate the supposed orbits of the sun and moon about the Earth. The hand with the sun, points to the hour and records three different kinds of time. The outer ring of medieval Arabic numerals measures Old Bohemian time, in which a day 24hours was reckoned from the setting of the sun. The ring of Roman numerals indicates the time as we know it. The blue part of the dial represents Babylonian time where the period of daylight was divided into 12 hours which vary from summer to winter.

The clock also shows the movements of the sun and moon through the 12 signs of the zodiac which were of great importance in 16th century Prague.

There is a procession of the 12 Apostles every hour, on the hour. It starts with the skeleton (representing Death) pulling the rope with his right hand and raising and inverting the hourglass with his left hand.Then the two windows will open with the Apostles taking their turns looking out the windows.