Prague’s Astronomical Clock

The Prague Astronomical Clock, or Pražský Orloj, is a medieval clock mounted on the southern wall of Prague’s Old Town City Hall. Clockmaker Mikuláš of Kadaň and Jan Šindel manufactured the Orloj’s astronomical dial just over 600 years ago in 1410. Despite being the world’s oldest working astronomical clock, the Pražský Orloj still provides an overwhelming amount of information.

This sophisticated clock’s dials, hands and markings display the times of sunrise and sunset, moonrise and moonset, the height of the sun at midday, the times of the solstices and equinoxes, how the Sun moves through the zodiac and how the Moon and the Sun move in the sky above them. It also tells the time—in three different ways! The Orloj is a beautiful and intricate representation of the human desire to understand and explore the heavens.

To see more photographs of this truly amazing clock, visit the Pražský Orloj | Astronomical Clock location page.