Truly prodigious water

Thousand-year-old water

The complex and fascinating process of the Boí Thermal water entails an intense circuit from its entry into the depths of the Earth all the way up to its re-emergence in the outside world, all of which takes place over a journey of thousands of years and kilometres.

Glacier water and rain water are the starting point for this hydrogeological process. This water, endowed with special chemical characteristics simply because of its origin, starts out on an intense subterranean journey through impermeable rocks and geological materials from the Earth’s crust and various layers of the lithosphere, which in turn bestow it with the chemical characteristics and temperature that makes it thermal mineral water.

In this sense, the thermal spring water from Caldes de Boí is the oldest water in the Pyrenees at over 16,000 years old.

Aguas mineromedicinales

Healing mineral water

Hot spring is the term given to subterranean water whose temperature is 5ºC above the average temperature of the superficial aquifers in the area. Mineral water possesses an abnormally high concentration of dissolved chemical substances. If the two characteristics are combined, both temperature and mineral concentration, the result is thermal mineral water. If said water is officially recognised as having healing properties, it is called healing mineral water. Nine of the 37 springs at the Caldes de Boí Spa have received this official recognition as healing mineral water thanks to their exceptional properties.

The transformation that this water undergoes to present these properties and classifications is a hydrogeological process through which each aquifer gains its own unique history.

The speed of the water along its route, the level of contact with the materials, and the characteristics of said materials are all key factors that contribute to the end result of the chemical composition and characteristics of the water.

The water that flows from the 37 Caldes springs, each with its own unique properties, has been on a 16,000-year journey through the depths of the Earth to return to the surface, transformed into sulphurous, ferruginous or carbonated water, depending on the chemical composition of each, with temperatures that range between 4ºC and 56ºC degrees.

The exceptional nature of Caldes de Boí is also due to this wide variety of springs, so unique that it was deserving of inclusion in the Guinness Book of World Records.

Boí Thermal uses the water from three of these 37 springs in its formulas:

Formulación del agua manantiales

Water from the "Font del Bou” spring

Hypotonic water with a consistent and exclusive composition. Rich in trace elements and a low mineral content. Has a unique concentration of silica compared to others on the market. This mineral acts on the structure that supports the skin, bestowing the water with regenerative and highly moisturising properties.

Water from the "Font del Boix” spring:

The most hypotonic water on the market with a consistent and exclusive composition. Its wealth of trace elements and low mineral content bestow it with soothing and moisturising properties, which help relieve redness.

Water from the "Font de la Tartera” spring:

Hypotonic and sulphurous water, it has been used since the 19th century for the treatment of dermatological conditions thanks to its chloride, sulphate, sodium and sulphur content. It is currently used to grow sulphurous algae for the production of Sulphaterm, a peloid (thermal mud) for application in dermatological therapies.

How does the Boí Thermal water affect the skin?

Active water

The Boí Thermal water is a unique healing mineral water that cannot be reproduced and maintains a constant mineral ion composition over time.

Thanks to its ion concentration and mineral profile, it provides the body with beneficial effects.

Water absorption

The stratum corneum is made up of dead cells embedded in a matrix of metabolically active substances that protect the epidermis and maintain its integrity. The epidermis has two mechanisms for absorbing substances. Water is absorbed via the transcellular pathway.

Water absorption

Hypotonic water, with a low ion concentration, encourages the water to penetrate the skin through the mechanism known as osmosis.

Hypotonic water
Ion concentration

Effect of the water

The penetration of water into the skin cells causes them to increase in volume and turgor. You will notice visibly softer and more flexible skin, as well as a wonderful feeling of comfort.

Water action

Differentiating between the types of water

Hot spring is the term given to subterranean water whose temperature is 5ºC above the average temperature of the superficial aquifers in the area. Mineral water contains an abnormally high concentration of dissolved chemical substances. If the two characteristics are combined, both temperature and mineral concentration, the result is thermal mineral water. If said water is officially recognised as having healing properties, it is called healing mineral water.