El Castillo, Chichen Itza

El Castillo (Spanish pronunciation: [el kas'tiʎo]), Spanish for "the castle"), also known as the Temple of Kukulcan, is a Mesoamerican step-pyramid that dominates the center of the Chichen Itza archaeological site in the Mexican state of Yucatán. The building is more formally designated by archaeologists as Chichen Itza Structure 5B18.