The ancient Maya pyramids of Chichen Itza, notably El Castillo (also known as the Temple of Kukulcan), are a significant example of Mayan architecture and astronomy. Built between the 9th and 12th centuries CE, El Castillo features a stepped design, four staircases with 91 steps each, and a temple on top. The pyramid's design reflects the Mayan calendar, with the 365 steps representing the days of the year.