Prague Astronomical Clock

The Wonderful Prague Astronomical Clock

Imagine a guy turning up at your office with an idea for putting a huge clock on the outside. It’s going to cost a lot of money, it’s going to break down a lot and only 3 people in the next 400 years will know how to fix it. Well the year was 1405, Mikuláš of Kadan was the guy and the city burghers decided to go for it. Now you have to know that over the previous 75 years the Old Town has been spending. It had bought three buildings, reconstructed two, demolished one and built the clocktower so they were not exactly short of money so this idea came at an opportune time.

prague astronomical clock and gothic doorway
Watch the Apostle procession everyday on the hour 9am to 9pm

The Basics

The geocentric Astronomical clock dial is at the top. The Calendarium is at the bottom. Often referred to as the Prague Astronomical Clock, in Czech the two combined are known as the Orloj. The clock tells accurate time according to the Roman numerals on the inside of the clock. On the outer ring of the clock are the numbers 1-24 which indicate the remaining daylight hours. The Calendarium has a fixed centre and pointer. It rotates clockwise once per day and points at a different area of the outer part which is divided into 366 sections and each has a name in it. For more info about part, check the Czech Namesday page.

The Prague Astronomical Clock Procession

If you want to see what the procession usually looks like then check the Astronomical Clock Striking 9am video.
On the hour from 9am to 9pm (all year) or 9am to 11pm (summer months) you have the procession on the Prague Astronomical Clock. You’ll notice that both the Clock and the Calendarium have characters on both sides. The ones either side of the Calendarium do not move. On the hour, the characters either side of the clock will start to move when the skeleton begins ringing the small bell. This causes the small windows above the clock to open and you’ll see the following apostles:

From the left window:
St. Paul holding a sword and a book.
St. Thomas carrying a spear.
St. Juda Tadeus holding a book in his left hand.
St. Simon follows holding a saw being (patron saint of lumberjacks).
St. Bartholomew appears with a book and is the patron saint of tanners, tailors and shoemakers.
St. Barnabas (Nathael) comes last carrying a papyrus.

From the right window:
St. Peter with a key (patron saint of fishermen, locksmiths and clockmakers).
St. Matthew with an axe (patron saint of builders, carpenters, blacksmiths and butchers).
St. John can be seen castigating a snake being the patron saint of printers and writers.
St. Andrew with a cross.
St. Philip with another cross (patron saint of hatters).
St. Jacob with a tool for working flax (patron saint of linen traders).

After you’ve seen one complete rotation of the apostles then the windows close, the skeleton stops ringing the bell and the cockerel crows. Then the big bell sounds the time in the 24 hour clock. The whole process takes between 60 seconds and two minutes.

The Prague Astronomical Clock is now over 600 years old and looked after full-time by a team of Orloj keepers. It’s been deliberately broken, accidentally broken, almost sold for scrap, survived fire and war and the odd stag night. So take a few minutes to enjoy some of Prague’s history. You’ll find the Old Town Hall and stories of the Orloj are on my Old Town and Jewish Quarter Walking Tour.

The Orloj keepers maintain their own website http://www.orloj.com/.

Prague Astronomical Clock

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