Answer: cenote

AnswerCrossword Clue
CENOTEUnderground reservoir: Sp.
CENOTENatural reservoir: Span.
CENOTENatural underground reservoir.
CENOTEDeep well used in Mayan rites
cenotedeep natural well or sinkhole, esp. in Central America, formed by the collapse of surface limestone that exposes ground water underneath, and sometimes used by the ancient Mayans for sacrificial offerings
cenotea sinkhole limestone