The Red King does his sacrificial rituals here. The Temple of Kukulkan, the Feathered Serpent God, is the largest and most important ceremonial structure at Chichén Itzá. The ninety-foot tall pyramid was built between the 11th to 13th centuries directly upon the multiple foundations of previous temples. Each face of the four-sided structure has a stairway with ninety-one steps, which together with the shared step of the platform at the top, add up to 365. The pyramid is oriented to mark the solstices and equinoxes. At the base of the northern stairway, a doorway leads to an interior staircase ending at a small, mysterious shrine.