El Castillo (Temple of Kukulkan)

El Castillo, also known as the Temple of Kukulkan, is a step pyramid at Chichen Itza in Mexico’s Yucatán Peninsula. It was built by the ancient Maya civilization around the 12th century. The pyramid features four staircases with 91 steps each, plus a final step on top, totaling 365 steps—one for each day of the year. During the spring and fall equinoxes, a shadow creates the illusion of a serpent descending the stairs, symbolizing the deity Kukulkan. The structure reflects Maya astronomical knowledge and religious beliefs, serving both as a sacred site and a demonstration of their advanced architectural and mathematical skills.