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Google Doodle: Prague's astronomical clock is 605 years old, but what makes it tick?
A new Google Doodle celebrates the Orloj, Prague's centuries-old - and still functioning - astronomical clock
Prague's astronomical clock, the oldest working clock of its kind in the world, has turned 605 years old, and Google has marked the occasion with a Google Doodle.
The ornate clock, known as the Orloj, is one of Prague's most recognised touristic spectacles, and is located in the Old Town Square in the centre of the city. Its hourly shows draw curious visitors from all over the world, where 12 apostles emerge from two windows to nod at the crowds below.
Other allegorical figures include Death, as a skeleton holding an hourglass, a miser with a purse of coins, a Turk shaking his head and Vanity peering into a mirror. The 12 zodiac medallions below the clockface itself were added by Josef Manes in 1865.
"Despite over a half a millennium of wear and a brush with disaster in WWII, much of its original machinery remains intact, making it the oldest functioning clock of its kind in the world," Google said.
"Today’s Doodle honors a magnificent achievement in medieval engineering and a cultural landmark whose symbolism, design, and intermittent repairs are a remarkable catalogue of Europe’s past."
The clock consists of two dials; the astronomical and the calendar dial. The former represents how the medieval world perceived the universe, with the latter's outer circle describing each day of the year.
It was once believed that clockmaker Master Hanuš created the timepiece in 1490, and legend has it the city councillors were so enamoured with it they had him blinded out of fear he should build another for a different European city. Distressed, Master Hanuš is said to have thrown himself into the clock mechanism, dying immediately.
However, a document unearthed in 1961 claimed the clock was actually made by a Mikulas of Kadan in 1410, in cooperation with astronomer Jan Sidel.
The most recent renovation to the Orloj took place in 2005, when the statues underwent some repair work. The city marked the clock's 600th anniversary with a light show depicting its creation and key moments in its history.
It is one of the buildings that can be viewed from the inside on Google Street View.