Turn your attention to the southern wall of the Old Town Hall, where you will see the world-famous Astronomical Clock, known locally as the Orloj. This masterpiece of medieval engineering was installed in 1410, making it the third-oldest astronomical clock in existence and the only one still operating with a significant portion of its original mechanical parts. It was created by the horologist Mikuláš of Kadaň and the mathematician Jan Šindel. Every hour, between 9 a.m. and 11 p.m., travelers gather to witness the Walk of the Apostles, where figures of the twelve apostles appear in the windows while a skeleton representing Death rings a bell. Beyond the show, the clock is a scientific marvel, showing the position of the sun and moon, the current zodiac sign, and even Old Czech time. Look for the four figures flanking the clock: they represent Vanity with a mirror, Greed with a bag of gold, Death, and Lust. For the best view of the crowd and the square from above, the Old Town Hall tower stands 70 meters tall and is the only historic tower in Prague equipped with an elevator for easy accessibility.