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Plan de Phasy

Holidaymakers who travel along the Durance valley to reach the ski resorts of the Forêt Blanche, Briançonnais, Guillestrois or Queyras have certainly passed by the Plan de Phasy, without suspecting that a major historical (and tourist) site for the Hautes-Alpes department was located there. These thermal springs, known and developed since Antiquity, continue to attract the curious and amateurs for their therapeutic virtues.

Hot springs

The water of Phazy flows through the Durance fault to come up from the bowels of the earth, at a depth of over 1000 metres. It gushes out at a temperature of between 26 and 28 degrees, and is naturally rich in iron oxide, silicon, calcium, magnesium, chlorides and sulphates. The presence of iron gives the water and the surrounding rocks a characteristic red colour.

Many therapeutic and even miraculous virtues are attributed to the waters of the Plan de Phazy. The various studies carried out since the 17th century have highlighted its qualities in relieving skin diseases, rheumatism and joint actions, respiratory infections and congestion.

The site of Plan de Phazy is made of two sources:

  • The source de la Rotonde
  • The source des Suisses (also called source des Vignes)

The water is pure, but not filtered against bacteria. Due to its temperature, it is recommended to not drink it.

From Roman baths to contemporary springs

The Plan de Phazy spring has been known for thousands of years. The Romans, who were sensitive to the virtues of hot springs, developed its waters very early. Indeed, the thermal site is located in the immediate vicinity of the Via Domitia, a road built in the 2nd century before the Common Era to facilitate the movement of the legionnaires who joined the Iberian provinces of the Republic (which will become later an Empire).

The name “Phazy” appeared during the Renaissance, but its origin has been lost. Oral tradition mentions Boniface, the first owner of the spring for the benefit of the hospitals built in the Middle Ages, of whom Phazy is the diminutive. Others claim that the name is a tribute to Pope Boniface.

The Rotunda, which you can still admire today, was built in 1824, during the reigns of Charles X and Louis XVIII. It was used as a place of reception and cure as part of a commercial operation of the site.

Take a bath in the Plan de Phazy springs

À l’origine, la source de la Rotonde jaillissait dans le bâtiment qui lui a donné son nom. Mais un séisme, survenu en 1935, a modifié le chemin de l’eau et la source jaillit dorénavant quelques mètres plus loin. Des bassins extérieurs successifs ont été aménagés pour permettre aux curieux, aux curistes et aux amateurs de profiter de baignades dans l’eau chaude, pédiluve. Les eaux de la source de la Rotonde sont accessibles par les quatre bassins situés en extérieur, tout au long de l’année et gratuitement.

La source des Suisses, d’un débit plus important, est canalisée et utilisée pour assurer le chauffage écologique de serres agricoles.

La Rotonde ne reçoit plus de baigneurs. Elle est néanmoins utilisée en saison estivale et accueille des artisans locaux.


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Une publication partagée par Naoo Bakoly (@naoobakoly)

A listed Natura 2000 area

The Plan du Phazy is located at an altitude of 900 metres, less than 2 kilometres as the crow flies from the stronghold of Mont-Dauphin. The unique properties of its salt-rich waters have enabled the development of unusual flora and fauna in this mid-mountain area. You can observe plants typical of salt meadows, such as the maritime spergularia, and animals and insects not common to this area, such as the Coenagrion mercuriale.

Its particularities have earned this exceptional natural and geological site a Natura 2000 classification.

Practical informations

The Plan de Phazy is located on the edge of the national road N94, which links Gap and Briançon :

  • In the direction of Briançon, a sign will show you the road to the site on the right.
  • In the direction of Gap, you can go around the roundabout towards Guillestre, then take the first road on the right (just before the supermarket). A small road on the left will lead you to the springs.