The Prague astronomical clock, or Prague orloj (Czech: Pražský orloj [praʃskiː orloj]), is a medieval astronomical clock located in Prague, the capital of the Czech Republic. The clock was first installed in 1410, making it the third-oldest astronomical clock in the world and the oldest one still working.
The Orloj is mounted on the southern wall of Old Town City Hall in the Old Town Square. The clock mechanism itself is composed of three main components: the astronomical dial, representing the position of the Sun and Moon in the sky and displaying various astronomical details; "The Walk of the Apostles", a clockwork hourly show of figures of the Apostles and other moving sculptures—notably a figure of Death (represented by a skeleton) striking the time; and a calendar dial with medallions representing the months.
The four figures flanking the clock are set in motion at the hour, these represent four things that were despised at the time of the clock's making. From left to right in the video, the first is Vanity, represented by a figure admiring himself in a mirror. Next, the miser holding a bag of gold represents greed or usury. Across the clock stands Death, a skeleton that strikes the time upon the hour. Finally, the Turk tells pleasure and entertainment. On the hour, the skeleton rings the bell and immediately all other figures shake their heads, side to side, signifying their unreadiness "to go."
There is also a presentation of statues of the Apostles at the doorways above the clock, with all twelve presented every hour.
