Fall Equinox in Chichen Itza

It's the fall equinox, and as is the case for both the fall and the spring equinox at Chichen Itza, the sunlight at noon will create a play of light and shadow along the side of the El Castillo pyramid, causing a serpent to appear along the staircase. El Castillo, also known as the pyramid of Kukulcan, was built by the ancient Maya and dedicated to the god Kukulcan, "feathered serpent." This building is evidence of Maya knowledge and concern with astronomy and the calendar. Besides its alignment with the sun on the equinoxes, the pyramid has 91 steps on each of its four sides, these together with the top platform make 365, the number of days in the solar calendar.

Chichen Itza was chosen as one of the New 7 World Wonders in 2007, and on October 4th, 2008, Placido Domingo performed a concert at this ancient site.

More about Chichen Itza:

• Chichen Itza Visitor's Guide
• Photo Gallery of Chichen Itza
• Spring Equinox in Mexico

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