Central to this story is where Anya goes missing. I did not know what a cenote was before reading this novel. A cenote is a natural pit, or sinkhole, resulting from the collapse of limestone bedrock that exposes groundwater underneath. Especially associated with the Yucatán Peninsula of Mexico, cenotes were sometimes used by the ancient Maya for sacrificial offerings.
What Anya intends to do in Mexico is cave diving. Cave diving is underwater diving in water-filled caves. It may be done as an extreme sport, a way of exploring flooded caves for scientific investigation, or for the search for and recovery of divers lost while diving for one of these reasons. The equipment used varies depending on the circumstances, and ranges from breath hold to surface supplied, but almost all cave diving is done using scuba equipment, often in specialised configurations. Recreational cave diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves decompression.
The place where Anya goes is Cancun. Cancún is a city in southeastern Mexico on the northeast coast of the Yucatán Peninsula in the Mexican state of Quintana Roo. It is an important tourist destination in Mexico.