Prague Astronomical Clock: The complete guide by a local

This my guide to the Prague Astronomical Clock. The oldest working astronomical clock in the world beguiles many visitors to Prague.

Most stop to see its famous hourly display of Apostles passing windows above the Clock. It’s a favourite with people of all ages, especially children.

We have lived in Prague for over three years, and watched this hourly event countless times.  The procession of figures has captivated people for over 200 years, but the original Astronomical Clock is over 600 years old.

Having watched this fascinating street theatre so many times, we thought it was time we wrote a guide to the Prague Astronomical Clock.

As well as its history, we show you the four ways it tells the time and date. We also advise you on how to get there, when to visit and offer a few local’s tips on enjoying it.

The Prague Astronomical Clock is a medieval masterpiece, and one of the best examples of its kind. It’s one of the foremost landmarks of Prague, occupying the base of the Old Town Hall Tower.

Watching the clock strike the hour is one of the most popular things to do in Prague. The procession of figures captures an audience every hour, and most, if not all, visitors see it at least once.

Seeing the Prague Astronomical Clock is one of many reasons to visit Prague Old Town Square. It’s the most famous of Prague squares and one of the most beautiful in the world.

The Prague Clock is first mentioned in a historical document in 1410, so it dates from either the late 14^th or early 15^th century.

It was initially built by clockmaker Mikuláš of Kadaň, with some input from Jan Šindel, a mathematician and astronomer at Charles University in Prague.

It was built at a time when it was believed the sun and universe revolved around the Earth, as opposed to the other way around.

The lower face of the clock – the calendar dial – was added in 1490. The stone Gothic sculptures were probably added around the same time.

The wooden figures were added during the 17^th century, and the wooden figures of the Apostles were installed during repairs in the late 18^th century.

Prague Old Town Hall is one of the most important Prague World War 2 Sites. The Town Hall suffered severe damage during the Prague Uprising in May 1945. Some parts of the building were destroyed and never rebuilt.

The Clock was badly damaged and had to undergo restoration afterwards, which continued into 1948, when the Communists seized power.

A message from a restorer from the 1940s was recently discovered inside one of the Apostle statues in the Clock.

In 2018, a message from Vojtěch Sucharda, who worked on the Apostle statues after the war damage, was found. In it he outlined plans for the Clock, which were never adopted. And he also complained about the Communists’ seizure of power.

It turns out that some of the 2018 restoration work may have been botched. The painting differs significantly from the previous Manes version, with some of the figures supposedly resembling the artist’s friends.

This was only picked up some years after the work – by the painter Stanislav Jirčík – was installed. It is going to be removed and replaced in 2024.

The Prague Astronomical Clock is an astrolabe as well as a clock. It tells the time, but also shows the position of the sun and moon in relation to the horizon.

The clock also tells the time of year by zodiac sign, and the lower face indicates the time of year with its painted calendar.

The Clock consists of several separate complex mechanisms working together. The clock face is in three colours – blue, red and black.

Blue indicates daytime. Red indicates sunrise and sunset and the time around each. Black indicates night-time.

The Latin word ‘Aurora’ in the left side of the red section means ‘dawn’ or ‘sunrise’. The word ‘Ortus’ above this in the blue section means ‘rising’.

The Latin word ‘Occasus’ on the right-hand side of the blue section means ‘sunset’. The word ‘crepusculum’ below this in the red section means ‘twilight’.

The hand with the sun indicates the time on the outer circle of the Clock. This, with 24 numbers on a black background, denotes Old Czech Time.  This is also known as Central European Time (CET).

The dial inside this, with Roman numerals, indicates Star Time.  Also known as sidereal time, this is based on when the vernal equinox passes the upper meridian. 

A day in sidereal time is just under four minutes shorter than a 24-hour day.

The next set of numbers inside the main face of the clock are Arabic numerals, the same as we use today. These indicate Babylonian time, running from 1 to 12. 

This way of telling the time is also known as Arabian time, or unequal hours. In layperson’s terms the daytime – between sunrise and sunset – is divided into 12 portions. These vary in length throughout the year, hence the term ‘unequal hours’.

The smaller circle within the larger one is the zodiacal ring, and is surrounded by the twelve signs of the zodiac.

The position of the moon is indicated by the small two-tone black and silver sphere near the outer edge.

The lower calendar face is a replacement of the original by Josef Manes – you can see this in the Prague City Museum nearby. The central plate is surrounded by a calendar of 365 saints’ feast days.

The Prague Astronomical clock has two faces. The upper one has a series of dials and is flanked by figures representing death, vanity, greed and lust. The lower face represents the twelve months of the year, and the figures either side represent virtues.

You can see it from outside – on Old Town Square – at any time of day or night.

A crowd usually begins to congregate below the Clock around ten minutes to the hour. Everyone is there to see the parade of figures as the clock strikes the hour.

As the Astronomical Clock strikes the hour, the two blue and white doors above the main clock open. A series of painted wooden figures – the Twelve Apostles – passes by these windows.

While this is happening, the golden rooster crows while the grinning skeleton figure on the right tolls his bell, warning of death.

The whole spectacle lasts around 30 seconds. It nearly always elicits a few cheers and a round of applause.

You can get up close to the figures of the Apostles if you visit the Old Town Hall Tower. You’ll need a ticket for this. You can see them on the first floor of the building, next to the Chapel.

If you’re there at the right time, on the hour, you can watch the procession of Apostles from up close, just a few feet away.

Firstly, get there five to ten minutes before the hour.

Ideally you want to be directly in front of the clock when it strikes the hour. If you’re a few metres off to the side, the view is not quite as good.

This can be a bit of a pickpockets’ haunt, so keep your bag zipped and locked, and don’t leave anything where it might be stolen. Street crime like this in Prague isn’t rife, but it can happen in popular areas like this.

Watch the Apostles’ parade, but also keep an eye on the skeleton below – we think he’s the star of the show!

Reward yourself afterwards with a coffee and slice of cake at the Café Mozart. It’s right opposite the Astronomical Clock, on the first floor of the Grand Hotel Praha. If you manage to get a window seat you have a superb view of the Clock and the Square below.

The Astronomical Clock is close to the base of the Old Town Hall Tower in Prague Old Town Square – Staroměstské náměstí in Czech. This is the focal point of Old Town Prague.

The Clock is on the south-facing side of the tower, so the sun tends to shine on it for much of the daytime.

The Astronomical Clock is easy to reach.

The Prague Metro line A stops at Staroměstská, which is on Kaprova, a 7-minute walk away from the Clock.

Prague tram 17 – one of the most scenic routes in the city – stops at the Staroměstská stop 50 metres further away from there. Trams 2 and 18 also call there.

To reach the Astronomical Clock, walk down Kaprova, cross to Náměstí Franze Kafky and into the Old Town Square. Once you reach the main part of the Square, turn right, continuing until you reach the Old Town Hall Tower. The clock is then on the wall on your right.

The only Prague public transport that goes any closer is the useful little 194 bus between Florenc and Mala Strana. It only stops in Old Town Square if travelling towards Florenc.

The Prague Astronomical Clock is slap-bang in the middle of the Old Town, within an area packed with places to see. It’s often full of tourists, but you don’t have to venture far to find some of the best hidden gems in Prague.

Old Town Square Prague is one of the most beautiful squares in Europe. It’s like a gallery of 800 years of architectural history, with outstanding buildings from the Gothic, Renaissance, and Baroque periods, and even some later Art Nouveau.

The most obvious landmark is the Týn Church Prague. Its fairytale Gothic spires dominate the Old Town skyline. It’s one of the most beautiful churches in Prague, its imposing Gothic walls concealing a fine remodelled Baroque interior.

Across the Square from there, the later Baroque St Nicholas Church is now the local Hussite Church.

15^th century preacher Jan Hus was a man ahead of his time, preaching values similar to those embraced during the Reformation a century later.

The fine Art Nouveau statue of him and his followers by Ladislav Šaloun dominates the north side of the square.

The Prague Jewish quarter of Josefov is a few minutes’ walk away up, a fashionable shopping street. The Prague Jewish Museum includes several synagogues and the beautiful Old Jewish Cemetery.

Old Town Square is around seven minutes’ walk from the Vltava river and the often overcrowded crowning glory of the city, Charles Bridge Prague.

How Old Is The Astronomical Clock In Prague

The first version of the Prague Astronomical Clock was completed by 1410. So it’s over 600 years old.  Some parts have subsequently been added and modified.

Who built the Astronomical Clock in Prague?

Mikuláš of Kadaň, with some help from Jan Šindel.

Is the Astronomical Clock in Prague free to visit?

Yes, it is free to visit. It’s on the exterior wall of the Old Town Hall Tower, a public space. You can watch the hourly display for free.

If you want to see the figures of the Apostles up close, you can do so with a ticket to the Old Town Hall and Tower.

When Is The Prague Astronomical Clock Show?

The display of the figures of the Apostles is hourly between 9.00 am and 11.00 pm daily.

Is there a replica of the Prague Astronomical Clock?

Yes- in Seoul, South Korea.

Seeing the hourly display of the Apostles is almost a rite of passage if you’re visiting Prague. The display is a bit of fun – you should see it once, but may not feel compelled to do so a second time. Having Our Little Man with me on my travels around Prague has meant I’ve seen it a great many times!

And if you get the chance, try to see it from the inside with your kids too.