The first nucleus of Périasc (Pèriâhc in patois) developed along the right orographic side of the Evançon. A path through the woods along the bank of the stream connects the two locations with a pleasant one-hour walk.
The settlement of Périasc seems to have very ancient origins, as suggested by the date (1517) carved into the stone frame of a window on Via della Neve, but recent dendrochronological investigations carried out on the wooden beams of some rascards could push its history back by at least another two hundred years.
In the village of Périasc, whose place name, according to Abbé Louis Bonin, author in 1928 of a pioneering guide to the valley, suggests proximity to water (Peri-asc, Per-aquas), there were two ovens, a mill, a forge, a cooperative dairy, and a mixed school founded in 1709. The memory of these buildings serving the community is still alive in the street names (Rue de la Laiterie, Chemin du For, Chemin de la Favergia).
The original chapel was replaced in 1860 by the current one, dedicated to Saints Peter and Defendente, at the wish of Archpriest Dandrès, whose work was always directed toward the interests of the entire Val d’Ayas.
The construction, at the end of the 1920s, of three famous hotels — Monte Zerbion, Monte Rosa, and Cime Bianche — marked a period of great vitality for mountain tourism.
According to tradition, an enormous landslide detached from the slopes of Mount Zerbion would have blocked the course of the Evançon stream and created a lake extending as far as Périasc. Geological investigations and studies have confirmed that the valley floor, in the stretch between Lignod and Extrepiéraz, is actually composed of ancient landslide deposits (paleolandslides) detached from both slopes, particularly from the eastern side of Mount Zerbion, which dammed the valley and consequently formed a lake basin extending up to Périasc, later filled in. Over time, the Évançon stream carved through these deposits to a depth of more than eighty meters.
Map of Périasc
Rascard
The subject of a restoration and renovation project is the large rascard behind Casa Obert Pitit, which bears the date 1761 engraved on a stone that was removed from its original location and repositioned on one side of the building itself. Its builders followed the architectural canons of the 18th century, which, building on models established in the late Middle Ages, introduced certain modifications to the floor plan, formal details and construction techniques. The logs are squared with an axe rather than simply debarked; the threshing floor remains in the centre, whilst the number of storage areas increases from one to two on each side, separated by a partition below the ridge beam. As in many rascards in the Val d’Ayas, the engraved trigram (IHS) is present. The original lock of one of the side doors is still visible in situ.

House Obert Pitit
Opening onto what was once the main street, this large stone mansion, with its views of the river and internal courtyard, is striking for its 18th-century architectural grandeur, typical of local noble residences. The street’s current name (Chemin de la Favergia) and the presence of a tall, imposing chimney suggest a change of use from a stately home to a blacksmith’s workshop. Above the door, traces remain of an 18th-century fresco that must have depicted the Madonna of Oropa with the Child, Saint Joseph and a saint (Saint Anne?). Before the painting deteriorated due to high humidity, a trefoil cross characteristic of the Order of Saints Maurice and Lazarus was visible on the Virgin’s robe, perhaps indicating that the patron who commissioned the image belonged to that Order. On the inner side of the house, above the wooden balcony, there are splayed windows edged in white, whilst a painted sundial, now illegible, once marked the hours. Part of the building was swept away in 1957 by the Evançon before the embankments were raised.

Chapel of San Pietro and San Defendente
Located in the centre of the village, it replaces the historic 17th-century chapel that once stood opposite the old bridge over the Evançon. Commissioned by the parish priest Dandrès between 1861 and 1863, as indicated by the inscriptions on the façade, it was decorated with frescoes depicting the two Apostles flanking the Virgin (the work of the Aosta Valley painter Franz Curta), as well as Saint Defendente, protector against avalanches and a warrior saint belonging to the Theban Legion martyred at Agaunum, now known as Saint-Maurice d’Agaune, in the Valais, in the 3rd century. Inside, there is a 19th-century wooden altar and two 17th-century statues, one of the Virgin Mary and the other of Saint Margaret, originating from the older building.

The origin of a name
There is a curious legend surrounding the origin of the place name Périasc. It is said that, during the Challant family’s rule in the Val d’Ayas, one of the sons of the Count of Graines, Asc (who never actually existed!), fell into the lake and that the lake was drained in order to recover his body. In memory of this tragic event, the village was named Périasc, the place where Asc lost his life (périt Asc). Scholars trace the ending -asc to the pre-Celtic Ligurian suffix -asco (common in the names of places near watercourses), referring to the characteristics of the place itself.
James David Forbes (1809-1868)
A physicist and glaciologist from Edinburgh, in one of his accounts of his travels in the Aosta Valley in 1842, describes this lake between Ayas and Brusson: “It was evidently the site of a lake formed by a massive landslide from the mountain on the right, which had thus dammed up the waters…”






