This natural well is 300 meters (984 feet) north of the main structures, along the remains of a sacbé (raised stone road) constructed during the Classic period. Almost 60 meters (197 feet) in diameter and 30 meters (98.4 feet) down to the surface of the water, it was a place for sacrifices, mostly to Chac, the God of Rain, who was believed to live in its depths.
The remains of scores of victims, mostly children and young adults, were dredged from the cenote, as well as innumerable jade and stone artifacts. On the edge of the cenote is a ruined sweat bath, probably used for purification rituals before sacrificial ceremonies.
The name Chichén Itzá  (Mouth of the Well of the Itzá) is surely derived from this deeply sacred cenote, and it remained an important Maya pilgrimage site well into the Spanish conquest.