The ancient Mayan site of Chichen Itza exemplifies the culture’s celestial orientation. The huge step pyramid (the pyramid of Kukulcan) that is the focus of the site has 91 steps on each of its sides, which add up to 364 steps. Adding the platform on top, there are 365 steps in total — the number of days in a year. Also, on the vernal and autumnal equinoxes (the first day of spring and fall, when day and night are the same length of time), the sunlight works to create a shadow of a giant serpent on the staircase that faces north.