This "sun stone" or calendar stone of the Aztec civilization depicts the sun god in the centre, surrounded by the four symbols of the Jaguar (top right, then clockwise), water, rain and wind. The band around the four symbols contains the pictographs of the 20 days. At the top of the stone is the pictograph for the number 13.
The stone, a basaltic monolith, is 3.7 m in diameter and weighs approximately 25 tons. The bar at the side is the size of an average human.
Museo Nacional de Antropología, Mexico City. Photo: G. and A. DeLange; public domain (Wikipedia)