It is a reservoir of spring water located in characteristic geological depressions, in which the water from the aquifer peeks out through the fall of the ceiling of a cave. It is part of the aquifers, which are interconnected between underground galleries. In a cenote, limestone or saskab rock (calcium and magnesium carbonates) predominates, favouring the formation of freshwater bodies typical of the Yucatan Peninsula (Mayan area). They can be found in other parts of America, usually at a certain depth.