Mounted on the southern wall of the Old Town Hall since 1410, the Prague Astronomical Clock is the oldest still-operating astronomical clock in the world and one of the most mesmerizing mechanical marvels of the medieval age. Every hour, crowds gather in Old Town Square to witness the procession of the Twelve Apostles as they glide past two small windows above the clock face, accompanied by the chilling figure of Death ringing his bell.

The clock itself is a masterpiece of medieval engineering and artistry, consisting of three main components: the astronomical dial tracking the positions of the sun and moon through the zodiac, the calendar dial adorned with medallions representing the months, and the animated figures flanking the clock face. The intricate mechanism was so prized that, according to legend, the clockmaker was blinded to prevent him from creating another.

Pro tip: Rather than jostling for space at street level, pay to climb the Old Town Hall Tower for a bird’s-eye view of the clock mechanism and a spectacular panorama of Prague’s spires and red rooftops. The view at sunset is particularly stunning and worth timing your visit around.