Caldas de Reis is a municipality in the north of the province of Pontevedra, in the autonomous community of Galicia, Spain.

[3] In the mid-6th century, the bishop's seat was transferred to Iria Flavia, now the Archdiocese of Santiago de Compostela.

Thus, no longer a residential bishopric, Caldas de Reis is today listed by the Catholic Church as a titular see.

The mineral content at Acuña is high in bicarbonate, fluoride, lithium, nitrogen, silica, sodium, sulphur, and radioactive elements.

[6] The mineral content from Dávila is high in chloride, nitrogen, sodium-rich, sulphur-rich, and radioactive elements.