Orrido di Pré-Saint-Didier

Where the Dora di Verney squeezes between rock walls below Pré-Saint-Didier, the water falls through a narrow ravine past the very cave from which the town's celebrated hot springs emerge. The gorge pairs Alpine geology with two millennia of thermal history.

Why it matters

The Orrido is the reason Pré-Saint-Didier exists as a spa town. This steep, nearly vertical ravine was carved by post-glacial erosion as the torrent descending from the Vallone di La Thuile cut into the rock, and at its base — beside the waterfall — rise the arsenic-ferruginous thermal waters, probably known to the Romans and certainly attested since 1560, that made the village famous. The gorge is thus both a natural monument and the physical source of the local economy: the same water that thunders through the narrows feeds the baths next door. The gorge brings together a waterfall, a documented thermal spring and a historic spa.

What to notice

Near the single-arch stone bridge over the Dora di Verney, two thermal springs emerge inside a sixteenth-century artificial cave; their water is cooler than the main springs, at around 22 degrees. The waterfall and grotto of the main thermal spring lie within the gorge, whose rock walls close to near-vertical. A cantilevered panoramic walkway above the gorge overlooks the waterfall and spring cave.

Context and history

The gorge belongs to the landscape history of the entire Valdigne. The Dora di Verney descends from the valleys below the Little St Bernard Pass, and its post-glacial downcutting left the ravine now called the Orrido — in French sources, the Gouffre de Verney. Human history clings tightly to the water: the beneficial springs at Pré-Saint-Didier are certainly attested from 1560, in a deed of enfeoffment, but are probably of Roman discovery, and from the mid-sixteenth century onward they anchored a flourishing thermal tourist trade that culminated in the 1834 bathhouse at the gorge's mouth. The sixteenth-century artificial cave by the bridge, where two of the springs were collected, is a rare survival of early modern hydraulic engineering in the valley. The ravine's waters continue to feed the spa below.