Stock Photo - The Sun Serpent The Kukulkán Pyramid Chichén-Itzá The Temple of Kukulkan, the Feathered Serpent God also known as Quetzalcoatl to the Toltecs and Aztecs is the largest and most important ceremonial structure at Chichen Itza This ninety-foot tall pyramid was built during the 11th to 13th centuries directly upon the foundations of previous temples The square base measures 55 3 meters 181 feet across Huge sculptures of plumed serpent’s heads sit at the base of the pyramid on the northern staircase At sunset during the spring and autumn equinoxes triangle shadows are formed by the platforms making it appear as if a plumed serpent is descending the pyramid