one of the major sights of the Prague
History of Prague Astronomical Clock
The oldest part of the Orloj, the mechanical clock and astronomical dial, dates back to 1410 when it was made by clockmaker Mikuláš of Kadaň and Jan Šindel, the latter a professor.
It is one of the most famous and oldest astronomical clocks in the world and is certainly one of the most sought-out of Prague's monument.
According to an old tale, the clock was built by mythic master Hanuš. Fearing that he could repeat his marvelous work for other cities, Prague's councilors are said to have assaulted and blinded the poor man. Master Hanuš, who suspected who was responsible for such a crude act, avenged himself - he inserted his hand in the machine and the clock stopped. For the next 100 years, it is said that nobody was able to repair Prague Astronomical Clock.
More information about Prague Astronomical Clock on Wikipedia