La Pirámide, known as the Temple of Kukulcán, is a Mesoamerican step-pyramid that dominates the center of the Chichen Itza archaeological site in the Mexican state of Yucatán. The pyramid building is more formally designated by archaeologists as Chichen Itza Structure 5B18.
Built by the pre-Columbian Maya civilization sometime between the 8th and 12th centuries AD, the pyramid served as a temple to the deity Kukulcán, the Yucatec Maya Feathered Serpent deity closely related to Quetzalcoatl, a deity known to the Aztecs and other central Mexican cultures of the Postclassic period. It has a substructure that likely was constructed several centuries earlier for the same purpose.
The pyramid consists of a series of square terraces with stairways up each of the four sides to the temple on top. Sculptures of plumed serpents run down the sides of the northern balustrade. Around the spring and autumn equinoxes, the late afternoon sun strikes off the northwest corner of the pyramid and casts a series of triangular shadows against the northwest balustrade, creating the illusion of the feathered serpent "crawling" down the pyramid.