Cenote
"(from Maya dz’onot), is defined as a natural well or reservoir, common in the Yucatán Peninsula, formed when a limestone surface collapses, exposing water underneath. The major source of water in modern and ancient Yucatán, cenotes are also associated with the cult of the rain gods, or Chacs. In ancient times, notably at Chichén Itzá, precious objects, such as jade, gold, copper, and incense and also human beings, usually children, were thrown into the cenotes as offerings. A survivor was believed to bring a message from the gods about the year’s crops". (Britannica, 2013)
Sources
Britannica, T. Editors of Encyclopaedia. "cenote." Encyclopedia Britannica, October 21, 2013. https://www.britannica.com/science/cenote.