St. Mark's Clock

This astronomical clock is in the Torre del' Orologio on St. Mark's Square in Venice, Italy. The original clock had concentric rings that showed the positions of the Sun, Moon, as well as the relative positions of Saturn, Jupiter, Venus, Mercury and Mars. The Roman Numerals show the hours of the day. During the 14th and 15th-centuries, these mechanical astronomical clocks were created in several European cities.