The Hontanilla Fountain was included in the catalogue of the Universal History of the Mineral-Medicinal Fountains of Spain of the 18th century. "The so-called Hontanillas fountain is born between rocks, to the south, and surrounded by leafy trees, it flows in a good quantity, its water is clear, thin, without smell, colour or special flavour. Ten pounds of it, with the evaporation, left a drachm and a half of residue, of which about four scruples were of whitish salt, somewhat inclined to yellow (...) All that has been said leads us to believe that these principles must be attributed to the virtues that the inhabitants of Corpa experience in the water of the Hontanillas fountain, which are that it moves their stomach, it is more digestive than the others and that in those who use it for some time, it deteriorates the strength."