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The pyramid and temple are about 2 1/2 hours by road from Cancun.

"According to legend, twice a year when the day and night are in balance, this pyramid dedicated to Kukulcan (or Quetzalcoatl), the feathered serpent god, is visited by its namesake. On the equinox Kukulcan returns to earth to commune with his worshipers, provide blessing for a full harvest and good health before entering the sacred water, bathing in it, and continuing through it on his way to the underworld."

Celebrations still take place today, but the human sacrifices and cutting out of the sacrificed people's hearts is no longer, because it's off-putting for the tourists.

"All legends aside, crafty and mathematically brilliant architecture combined with the natural rotation of the earth creates an amazing and somewhat eerie image of a giant snake crawling down the temple. For five hours an illusion of light and shadow creates seven triangles on the side of the staircase starting at the top and inching its way down until it connects the top platform with the giant stone head of the feathered serpent at the bottom. For forty-five minutes this impressive shadow stays in its entirety before slowing descending the pyramid and disappearing along with the crowd that gathered to see it."