Legend has it that in the Middle Ages, there was a clockmaker so talented that he created the most beautiful clock in the world, one that perfectly measured time as well as the movement of celestial bodies. To ensure that the clockmaker would never again recreate such a treasure for anyone else, his commissioners had him blinded. Ever since then, the clock has been cursed.

That’s one version of the many stories told and retold over the ages about Prague’s iconic astronomical clock (orloj in Czech), which has been keeping track of the universe from the southern wall of the city’s Old Town Hall for over 600 years. In early January, the city of Prague announced that it would temporarily take down the Orloj for repairs. While the clock is scheduled to return to the Old Town Square (Staroměstské náměstí) at the end of August, we thought we’d use its temporary absence as an opportunity to trace the history of one of the oldest astronomical clocks in the world.

The Orloj dates back to 1410 CE, when imperial clockmaker Mikuláš of Kadaň created the original masterpiece for the city’s center, with the help of astronomer/priest Jan Šindel. Originally, the clock kept time and followed astronomical movements. In the next few centuries, additions were made to further embellish both its operations and aesthetic. The clock currently has numerous functions, including tracking Old Bohemian time (when day began at sunset), Babylonian time (sunrise to sunset), Central European time (marked with the hand shaped like a sun), and Star time (based on the movement of the stars, and slightly shorter than solar time). It also includes a ring for the zodiac and a calendar dial, as well as an astrolabe, tracking the position of the sun, moon, and stars.

Today, the most popular — let’s face it, the most accessible — aspect of the Orloj is its animated decorations. Every day right before noon, hoards of people gather in front of the clock and wait for it to strike, at which time sculptures of the Twelve Apostles take turns peeking through two windows at the top of the clock. Below them, a skeleton representing death pulls a bell, while the three figures of the miser, vanity, and “the Turk”— remember, much of Central and Eastern Europe was once ruled by the Ottoman Empire — nod to each other in a kind of morbid understanding.

Over the centuries, the Orloj has had many different caretakers. The current clockmaster, Petr Skala, has been in charge for the past eight years, according to a Marc Santora article published in mid-January in the New York Times. The 71-year-old Skala, who as a child would take clocks apart for fun to see how they work, is in charge of the Orloj’s renovations, replacing some of the more modern gears with a system closer to the original design and restoring the various parts to their original colors.

According to Deutsche Welle, this is the clock’s first complete reconstruction since WWII (a shocking 3/4 of the clock’s components remain from the original), when during the Prague Uprising of May 1945, the Nazis destroyed much of the Old Town Hall, badly damaging the Orloj with an incendiary shell. But the clock was back in business by 1948, with sculptor Vojtěch Sucharda restoring the badly burned apostle figures. In 1957, Old Bohemian time was added to the clock, and in 1976, the original sculptures were taken down and moved to the Prague City Museum for safe keeping, replaced by copies on the Orloj. As for the curse of the Orloj, by now it seems to have been all but forgotten. But we should probably wait until the end of the summer before saying anything conclusive, just to be safe.