Astronomical Clock

The Astronomical Clock on the Old Town Square is Prague's most iconic sight. Every hour, the clock draws so many tourists that it's impossible to miss. The spectacle lasts less than a minute. What's special about this clock is that almost no one can actually read the time from it. It requires a deep understanding of the clock. YOU LOVE PRAGUE is happy to explain it, though it remains quite tricky.

The Oldest Working Astronomical Clock in the World
The Astronomical Clock has adorned the Old Town Hall since 1410, making it the oldest working astronomical clock in the world. It was designed by Nicholas of Kadaň based on the calculations of Professor Jan Sindl.

Over the centuries, more elements were added. The clock has stopped working several times, undergone multiple restorations, and was damaged by bombings during WWII.

Personal Tip

"Join the crowd, get your camera ready and enjoy the show while it lasts."

The Astronomical Clock in Action

You unsuspectingly walk onto Prague's Old Town Square, amazed by its beauty. Everywhere you look, you're surrounded by architecture with a capital "A" - colourful monumental buildings, with a large statue of Jan Hus and the Marian Column in the middle of the square. This means it’s almost time… five minutes until the hour.

Then, near some overpriced terraces, you notice a large crowd gathering, phones and cameras at the ready. Most are looking slightly upwards.

What are people looking at?
They're gazing at a magnificent timepiece, one that is worth a photo even without the upcoming spectacle. Without any background knowledge, many people react to the show with comments like those you’ll find in some Google reviews:

From "Hmm, was that it? Nothing special!" to "It's a tourist trap for pickpockets."

That’s why it’s worth reading the following basic explanation to grasp just how complex the clock and its mechanism are. Then, it becomes a true masterpiece.

And keep in mind that this is handmade craftsmanship from a time when there were no computers, calculators, or electric tools - let alone tourists with phones equipped with cameras.

The Components of the Astronomical Clock

How can you read the time?

On the non-rotating part of the clock, Roman numerals indicate the hours (two times I to XII).

The golden hand at the end of the clock's arm, which also holds the sun, points to the time. In the following photo, it is approximately 5:10 PM.

When the Roman numerals are obscured, as seen in the photo, the time can be determined from the extension on the opposite side of the clock face. There, the hand is positioned between V and VI.

The numbers on the outer rotating dial (1 to 24) indicate Old Bohemian time. In this system, a new day began at sunset (24).
The numbers from 1 to 12 in the blue area represent the lesser-known Babylonian time.

What do the colors blue, red, and black represent?

On the non-rotating part of the clock, you can see three colors: blue, red, and black.

Blue represents day, red stands for dawn/twilight, and black symbolizes night.

On the border between the blue and red areas, you can see four Latin terms:

Ortus (sunrise)
Aurora (dawn)
Crepusculum (twilight)
Occasum (sunset)

The Golden Sun, the moon and zodiac signs

The golden sun on the dial with the golden hand moves towards the end of the arm after the shortest day of the year. The sun rises earlier in the morning and sets later in the afternoon/evening in the red area.

After the longest day, it gradually shifts closer to the center of the clock. At this point, the sun rises later in the morning and sets earlier in the red area.

The moon on the second hand indicates the phase of the moon.
The small disc features twelve zodiac signs representing the months of the year.

The calender dial

Below the clock face, you see the calendar dial with twelve allegories representing the months. This was created in 1865 by Josef Mánes. It is a replica; the original is housed in the Museum of the City of Prague.

With the naked eye, you cannot see what is written in the gray outer ring. When you zoom in, you can see:

The day of the month
A letter, A to G, representing the days of the week
The name of a saint after whom the feast day is named.

The outer ring contains syllables that together form a mnemonic text for remembering the names of the saints’ days (which is difficult to see).

Details of the calendar board

The names of the saints

One of the allegories

Next to the Calendar Dial, You see two sets of two figures

Left Side:

A philosopher exploring the world
Archangel Michael

Right Side:

An Astronomer / stargazer observing the heavens
A chronicler recording events and history

The one minute show spectacle

The parade of the apostles

The show is about to happen. Are you ready?

The crowd is ready, you are excited and you can feel the high level of expectations of the crowd hanging in the air. Now it's time to get your camera. Suspense, time goes by and there it is.

The show begins:

As Death (the skeleton) pulls the bell to signify that another hour of your short life has passed, the little doors above the clock open.

In a parade, the twelve apostles appear on stage, nodding as they pass by from left to right. They were added in 1865 together with the calendar dial. After all the apostles have made their appearance, the doors close and the golden rooster has its one shot at its second of fame: it crows one time.

After this fantastic show, the bells of the tower chime to indicate the hour.

Wow, just wow.

At that moment, when the show is over, listen to the disappointed sighs of the crowd. But you know better...this is a piece of medieval art.

Two of the main characters in the show

Personal Tip

"Be sure to stand in front of the clock between 8:00 AM and 11:00 PM;

otherwise, you’ll only hear the clock strike.

If you want to see what it looks like inside, buy a ticket for the Old Town Hall."

Four Moving Figures

On either side of the clock, you see four figures stealing the show.

Death - Skeleton

Death is characterized by a skeleton with an hourglass, which he turns as a symbol of measuring the time of life. With his ringing and approving nod, he reminds everyone of their inevitable fate. The figure of Death has been the oldest component of the figurative decoration of the Astronomical Clock since the end of the 15th century.

The Turk - Lust

Next to Death stands the Turk. He is depicted with a lute and symbolizes extravagance, lust or pleasure in the sense of human vice.

The Miser - Greed

The Miser is characterized by a staff and a bag (of money). In addition to shaking his head disapprovingly, he threatens with the staff and shakes the bag. He symbolizes vice and greed.

Vanity

Vanity is characterized by a mirror. The wooden figure shakes its head disapprovingly while simultaneously gazing into the mirror. It is generally regarded as a symbol of human vanity.

The clock was almost written off
The Astronomical Clock stopped working in 1787. It was almost sent off as scrap, but was partially repaired. In 1824, the clock completely ceased to function. At that time, no one could repair it, and it was decided to remove it.