One of the 7 new wonders of the world.
Dominating the center of Chichén is the Temple of Kukulkan (the Maya name for Quetzalcoatl), often referred to as "El Castillo" (the castle). This step pyramid has a ground plan of square terraces with stairways up each of the 4 sides to the temple on top. On the Spring and Fall equinox, at the rising and setting of the sun, the corner of the structure casts a shadow in the shape of a plumed serpent - Kukulcan, or Quetzalcoatl - along the side of the North staircase. On these two days, the shadows from the corner tiers slither down the northern side of the pyramid with the sun's movement.