Prague Astronomical Clock

Origin and History of the Clock

The Prague Astronomical Clock is the world's only medieval orloy using original parts which is still in operation. You can find it on the Southern side of the Prague Old Town Hall’s tower and identify it by the huge crowd of tourists from all over the world gathered in front of it. It is the single most popular sight of Prague.
The Clock was built in 1410 by Mikulas of Kadan and perfected at the end of the 15th century by master Hanus of Rose. It was repaired by clockmaster Ludvik Hainz in 1865 who became its caretaker together with his descendants since then. The clock engine survived all the centuries and remains in full operation today.

The Prague Astronomical Clock is made up of three parts: the Astronomical Dial showing four kinds of time in the middle, the Calendar Dial with round paintings representing the 12 months at the bottom and balcony with windows and parade of mechanical figures of the 12 Apostles at the top.

The Apostles Section and other Figures

Every hour from 9.00 a.m. to 9.00 p.m., the 12 apostles, each carrying his attribute, appear in the two windows below the small roof in the upper part of the Clock. In the left window, viewed from the visitors, the first to appear is St. Peter with a key, then St. Matthew with an axe, St. John with a chalice, St. Andrew with an X-shaped cross, St. Philip with a cross. St. James with a washboard, and in the right window, it is St. Paul with a book, St. Thomas with a spear, St. Simon with a saw, St. Thaddeus with boards, St. Bartholomew with leather, St. Barnabas with a scroll.

All the wooden figures presented on the Astronomical Clock were destroyed during the fire in May 1945. The original figures from the early-Baroque period have been partially preserved in the Museum of the Capital City of Prague. They were replaced by wooden statues of apostles made by woodcarver Vojtech Sucharda in 1948.

When the parade of the 12 Apostles starts showing, also the figures standing on both sides of the Astronomical Dial start to move. The Skeleton pulls the rope and starts the Apostles’ walk in the two windows via ringing. He nods towards the Turk - allegory of Lust, who refuses by turning his head. The Miser - allegory of Miserliness - nods his head with a pouch in his hand and shakes his cane in a threat, and the Vain man next to him - allegory of Vanity - looks at himself in the mirror. The Rooster in the window crows when the windows close - he awakens for another hour of life and the bell on the tower starts to chime.

The Calendar Dial Section

There is nothing so special to it. There are immovable wooden figures installed at the level of the Calendar Dial, named Philosopher - allegory of Philosophy - with a pen feather, Astronomer - allegory of Astronomy - with a telescope, Chronicler - allegory of Rhetorics - with a book, and Archangel Michael with a fiery sword.

The Calendar Dial with allegories of months has been created in 1865 by Josef Manes. Its original is deposited in the Museum of the Capital City of Prague, and there is a copy of it created in 1946 instaled on the town hall.

The Astronomical Dial Section

This is where the magical medieval engine shows four kinds of time and displays astronomical data. The movement of the figures is formed similarly to that of a cuckoo bird in the cuckoo clock. The mechanism is placed in the town hall’s wall in a stone spire to which there are two keys: one for the caretaker, the second stored at the magistrate. There are lots of functional original parts in the machine. It is a matchless and unique technical relic. Before the end of the Second World War, the astronomical clock was wounded via a crank, then it was connected to an electric motor. Big Ben in London works on the same principle.

The Astronomical Dial shows four different times

The Central European Time (Old-German) is shown by the Sun Hand and marked by Roman numbers on the sphere’s perimeter. The Clock only started to measure this time after the reconstruction in 1948. Apart from that, the clock shows the Old-Bohemian time where the new day starts with the sunset (golden Gothic numbers in a separately controlled ring outside the sphere) and the Babylonian time (unequal) where the hours last longer in the summer than in the winter, because this time is measured from the sunrise to the sunset. Prague Astronomical Clock is the only one in the world capable of measuring this time. Star time is displayed on the Roman numbers. There is a calendar dial in the lower part of the facade. It shows the day and its position within a week, a month and a year.

The Astronomical Clock celebrated 600 years of operation in 2010.