This is the famous Astronomical Clock in Prague. It's more than 600 years old and very hard to read. But not that much if you have a guide to explain the clock for you ...

This is an astronomical clock made by Song I-yeong, who was an astronomy professor in 1669 during the reign of King Hyeonjong of Joseon. The diameter of the clock is 40 centimeters (15.74 inches ...