Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
SoufreSulfuresSulfates
The Thermal Spring of Pré-Saint-Didier is a natural sulphurous geothermal spring in the Aosta Valley, Italy, where hot spring water at around 36°C emerges from deep fissures in the granite basement of the Mont Blanc massif, feeding the elegant Terme di Pré-Saint-Didier spa — one of the highest and most scenically situated thermal resorts in the Alps, with views directly toward the southern face of Mont Blanc. The spring, used since at least the 16th century, has been developed into a beautifully designed contemporary wellness centre where outdoor pools, terraced on the mountainside, allow bathers to soak in hot sulphurous water while contemplating the snows of Mont Blanc, Monte Rosa, and the Grandes Jorasses. The combination of extraordinary alpine scenery and quality geothermal spring water makes Pré-Saint-Didier one of Italy's most spectacular and memorable thermal destinations.
Insider tip — This natural sulfurous spring emerges at 37°C at the foot of the Mont Blanc massif, just a short walk from the famous Pré-Saint-Didier thermal complex. The water seeps through schist and gneiss of the Pennine Alps, picking up sulfur compounds along its deep underground journey. The wild source lies in a gorge carved by the Dora di La Thuile torrent, framing snowy peaks year-round. Pair a soak here with the formal spa pools just up the road for a full thermal experience in the heart of the Valle d'Aosta.