The world-famous Prague Astronomical Clock ("Orloj" in Czech) is one of the major landmarks of the city. Hundreds of thousands of tourists come from all over the world to see it. But you may not believe that some 250 years back it was almost discarded as scrap!
Luckily, now it's acknowledged to have huge historical value. It is hard to precisely reproduce the state of clock engineering in the 14th century, but most probably Prague Astronomical Clock is unique by the combination of age, complexity and size. There were earlier clocks in Europe, most notably in Italy, but they are simpler. There are clocks of the same complexity, but they appeared later.
But let's start from the beginning.
Where is Astronomical Clock (Orloj) located
Its alternative name - Old Town Astronomical Clock - depicts its location pretty well. It is located on the tower of Prague Old Town Hall, which is, naturally, located on the Old Town Square.
Prague Astronomical Clock history
Here, we should start with "history of the history". Because the clock is so old that "it was always there" and at some point no one knew when it appeared, who were its initial creators, what changes and improvements it underwent through the centuries. Even so that in the late 18th century it was in such a poor state that city council was going to decommission it. Luckily, someone came forward who realized its value and convinced the city council not only to keep it, but to sponsor its repair.
Once started the Czech National Revival, patriots got interested in the history of the nation and monuments. First research, carried out by the writer Alois Jirasek, reached back to the year 1490 and master Hanus, whom he declared to be the creator of the clock. And to bring more attention, he applied a widespread tale about how the author of an outstanding masterpiece was then blinded so he could not reproduce this masterpiece, to this master Hanus. Later researchers dug deeper into the archives and found the document, describing the newly-created clock in detail and the reward for its author, dating back to the year 1410. So this year is believed to be the year of origin of the clock, and its creation is attributed to the clockmaster Mikulas from Kadan and the dean of Prague University Jan Sindel.
During its history, the clock underwent many changes and repairs, which are documented to different degrees of precision. First, invisible but crucial inner mechanics were totally replaced in the 19th century with way more precise one; then in 1948 it was replaced with an electric engine; and, finally, in the beginning of 21st century original mechanics were restored, but controlled by electricity and not gravity.
The look of the clock changed as well. First, in the year 1490 the lower (calendar) dial was installed. In the 17th century, it was decorated by allegoric wooden figures. Later, in the 19th century, the figures of the 12 apostles parading each hour from the windows above the upper dial, were introduced. And in 1865, the modern variant of the calendar dial was made by the painter Josef Manes (though changed several times since then).
During 20th and 21st centuries, the clock underwent several major repairs, one of them after it was severely damaged during Prague uprising in May 1945.
How to read Astronomical Clock
Though most of the people gather around the clock to watch hourly parade of the figures of saints, the true value is the clock itself. Yes, you can read time from it too. But it's not that easy, and it shows a lot of other things.
First, it does not have second or minute hand. It has three hands: sun, moon, and star. Since the daytime relates to the position of the Sun, respective hand shows the daytime (just hours). But not just: it shows how high the Sun rises above the horizon; how many hours are left until the sunset; which part of the sunlight time has already passed. And the same for the moon: you can understand the relative position of the Moon and the Sun, how high the Moon rises, which zodiac sign it is in.
Then, not only the hands are moving: the zodiac dial moves together with the star hand (naturally, they belong to the same sphere), and the outer ring divided into 24 hours changes its position throughout the year, because 24 hours there means sunset.
If you wonder, why the heck you would need to know all that while minutes and seconds are omitted and you may miss your business meeting if you rely on it, read on.
Machine from another Universe
To understand the clock, you need to understand the time it was created. It was literally another universe. First, most people were illiterate. But everyone knew that the Earth, the Sun and the Moon, and stars were created in a 6-day span by almighty God. Educated people knew, that the Earth was in the center of the universe. Around the Earth 3 spheres were rotating: one with the Sun, another one with the Moon and the third one - with the stars. No one could even think that there were stars they could not see.
The skies were much closer. Now, to see the star-clad sky, we need to travel to a desert or the mountains to escape light pollution. At that time, stars were always there. And in the absence of mass-media and even football competitions the sky was one of the rare spectacles. And at the same time it was the most precise and available instrument: it was showing the direction for travelers, it was instructing farmers about the timeliness of their work. It was, actually, defining everything - the reliability of astrology was undisputed at that time.
So, the Astronomical Clock (or, better, astrological for that time) was a mechanical reflection of the Ptolemaic geocentric system. And no one cared about minutes or seconds at that time.
When to come and what to see
So, it's a landmark not to miss in Prague. But to get the full value of it, either do some reading beforehand or go with a knowledgeable guide. Within our Historical walk tour, we make a stop at the Astronomical Clock and spend some time looking at the details and understanding the whole message they convey. Most of the people come just for the hourly apostles show, which, with all due respect, is neither unique nor exquisite (and it runs only in the daytime, from 9am to 10pm. If you come at 7am, you'll be disappointed).
Besides the clock construction and all the wealth of information they provide, the Gothic griffins around the clock are worth attention, along with a number of allegoric wooden figures from the 17th century.