Its thermal waters are recognized for their therapeutic properties to treat diabetes, digestive problems, respiratory ailments and the osteoarticular system, attracting many visitors in the 19th and 20th centuries.

[1] On 1 May 1894, the Empresa Santos, Sobral & C.ª was constituted with investment capital of 20 contos, of which a portion was conceded legally to the older concessions António Cândido de Sousa and Castro Morais Sarmento.

[1] By 1895, a hotel already dominated the land, constructed by António Guerreiro Ranhada, who had returned from Brazil and discovered that the waters were a therapeutic cure for his liver problems.

[1] On 3 July 1898, the Ministry of Public Works ratified the concession attributed to Santos, Sobral & Co., providing the company with all the rights to explore the spring in perpetuity.

Yet, on 11 November 1904, a dispatch delivered to the Empresa Santos, Sobral & Co. a reserved perimeter of 15 hectares for the exploration of mineral springs, allowing the company to begin its expansion.

[1] This work, begun in 1909, was under the direction of engineer Couto dos Santos, for a cost of 43 contos, with testing of the water undertaken by professor Charles Lepierre and Dr. António Cruz Magalhães.

[1] By August, the management presented to the Repartição de Minas a plan to improve the thermal spa, under the authorship of engineer Couto dos Santos, that included the expansion of the Quinta do Peso lodgings, in accommodate 350 visitors, the construction of a casino, a gymnasium and hydrostatic lake served by swimming huts.

[1] In July 1921, a description of the waters in Melgaço described:[1] Hypothermal-Hypomineralized, Gaseous carbonate and bicarbonate, with a mix of Calcium and Sodium, Iron and Magnesium...Util for general illnesses (diabetes, arthritis, etc.

and nervous system (Neurasthenia, hysteria, etc)... By 1924, the changing areas were completed, at a time that the Thermal Park was delimited, under the work of landscape architect Jacinto de Matos, that included large trees (maples, faia, cedros and tílias, among others).

[1] Notice on the opening of the change rooms was issued on 8 June, under the direction of Dr. Athias Ark, in addition to providing information on pricing practiced at the site.

[1] An article published in August, by the Notícias de Melgaço, referred to the avenues of the park that crossed the property east to west, that connect a new spring that had been discovered, covered in a wooden structure.

Following their acquisition, a new analysis of the waters by professor Herculano de Carvalho, referred to the existence a variation in the alkalinity in the two springs, that included magnesium, silica and carbon dioxide.

[1] The thermal park and spa are located in isolated urban context surrounded and delimited by walls surmounted by grade and crossed by the Ribeira da Folia.

[1] It is implanted to the left of the Estrada Nacional E.N.202, running west to east, while nearby are situated the Pensão do Peso and in its northwest interior the Ponte da Folia.

In the centre of the building is the primitive buvette thermal spring recessed into an octagonal plan with similar pavement, and protected by iron grate, painted green (with faceted basins on angles).

Around the building is a raised wing, accessed by an intermediary landing of stairs, with black and white ceramic floors and iron guard painted green, decorated by stylized voluptuous motifs.