Chichen Itza was one of the largest Maya cities. El Castillo or Kukulcán’s pyramid is essentially a nine-step structure culminating in a flat platform that supports a two-story temple. El Castillo’s design is thought to relate to the Mayan calendar.
Each of the four faces incorporates a broad, steep staircase consisting of 91 steps that ascends to the top platform. Counting the top platform as an additional step gives a total of 365 steps: 1 step for each day of the year.