High-altitude calcareous environments around Lake Tsan

Here lies a high-altitude setting which expands between the valleys of Saint-Barthélemy and Chavacour, in the municipalities of Nus and Torgnon, where you can find natural habitats of main interest for the preservation of biodiversity; these include petrifying springs with travertine formation, pioneer formations of the Caricionbicoloris – atrofuscae, calcareous floors and herbaceous formations in Nardus. In this setting, on the slopes of the Cima Bianca in the high valley of Torgnon, you will find Lake Tsan (2.442 m), a true karstic area engraved in the torrent of Chavacour which descends from the basin of its homonymous Pass. The torrent is characterized by a rare phenomenon: its waters disappear suddenly in a natural cavity set at an altitude of 2.530 m, called Borna di ciove (hole of the choughs), where choughs enter the cave in summer to seek freshness and refuge. Lake Tsan is a true mirror of alpine water, with changing colours, dominated by fabulous peaks, including those of Punta Tsan, Punta Chavacour, Cima Bianca, up to Gran Tournalin and Gran Sometta. Magnificent views and wild corners create its scenery and from here depart many climbing trails. The overlaying plaques of Rey to Punta Tsan, for example, were test-beds for illustrious climbers, among whom princess Maria José who defied them in September 1941 to prepare her ascent to the Matterhorn, which she accomplished later the same year on September 11th. From a botanical point of view, the high-altitude flora, even though of reduced dimensions for its environmental adaptation, offers spectacular colours. Among the most interesting and rare species, you can encounter white-flowered Ranunculacae, like the Anemone baldensis and the Callianthemum coriandrifolium, as well as the less ostentatious Carexrupestris and Saxifragamuscoides. The fauna is also typical of alpine environments and it is not rare to observe the Golden Eagle which hovers over these environments inhabited also by the Eagle Owl, the Chough, the White Grouse, marmots, stein-bocks and variegated hares.


  • Hiking

    All itineraries are described in the TRAILS section.

  • Mountain Biking

    Mountain bikers and horseback riders can use the dirt roads of the surrounding area, all external to the site, which reach the municipalities of Saint-Barthelemy and Verrayes, set at higher altitudes.

  • Horseback Riding

    Horseback riders can use the dirt roads of the surrounding area, all external to the site, which reach the municipalities of Saint-Barthelemy and Verrayes, set at higher altitudes.

Discover the site

Summer months are best to discover this vast land, also because in winter, the roads are often inaccessible due to massive snow accumulations. July and August are ideal for their magnificent high-altitude blossoming. The site’s access trail, though without apparent difficulties, is rather long (almost 3 ½ hours) and is thus recommended to well-trained or expert hikers.

Behavioural conduct rules

We remind you that you can contribute to the preservation of these sites by following these simple rules:

visit the site on foot, with skis or snowshoes; avoid using motorized vehicles, boating equipment, hang-gliders, para-gliders or similar; mountain bikes and horseback riding are permitted only in specific authorized areas (external to the site): please respect hikers;

please stay within the marked trails, as trampling can ruin the fragile grass and undergrowth areas; in winter, please follow the recommended trails so as not to disturb animals which are fighting against hunger and cold;

please observe wild animals from a distance, do not capture them, do not disturb them nor feed them, and do not photograph occupied nests;

keep your dog on a leash and on the marked trails;

do not pick minerals or flowers;

do not make fires;

please bring your garbage back to the villages, where you will find many recyclable waste-collection points;

camping is permitted only for nightly bivouacs at an altitude of over 2500 meters; take care not to wash your dishware in springs or stagnant ponds of water; campers and trailers must be parked outside of the park, in specific authorized areas.

How to get there

By car

The site’s main entrance can be reached from the municipality of Torgnon: you must travel along the S.R. 46 regional road from Chatillon to Valtournenche; at the height of Antey-Saint-André, take the SR 9 state road which brings you to Torgnon. Once you have reached the village, continue towards the hamlets of Septumian, then pass the well-equipped picnic area of Plan Prorion. Once you have passed the soccer field, you exit the forest and after a few turns, you can reach the hamlet of Champtorné, at the level of the first ski installations of Torgnon; in the vicinity of the “Lo Vierdzà di Champtorné” bar/restaurant, signs indicate that cars are no longer allowed access and thus you must continue on foot. The site can also be reached from the Valley of Saint-Barthélemy, in the municipality of Nus, but it requires a long walk on a farm path, up to the Tza de Pierre alp, before taking the trail towards destinations such as Finestra di Tsan.

By bus

The Chatillon-Torgnon busline is available.

Accessibility codification of sites

VIVA has chosen to supply everyone – youngsters, adults, the elderly and the disabled – with all the sites’ information so as to allow the visitor to choose a destination in an autonomous way.
An “Accessibility Codification”has thus been defined.

High-altitude calcareous environments around Lake Tsan

Information to reach the site 1
Accessibility from main roads 1
Parking for the disabled 2
Accessible restrooms 1
Information panels 1
Slopes (max 8%) 0
Trail width (min 90cm) 0
Road surface 0
Resting areas approx every 10 m 0
Safety and protection of trails 1
Periodic maintenance 1

0 corresponds to ABSENCE of the indicated parameter;
3 corresponds to the PRESENCE of the indicated parameter, in optimal condition;
1 – 2 are INTERMEDIATE VALUES: in general, they indicate the presence of the parameter which must however be improved (1 = sufficient, 2 = close to optimal)


More paths :

VIVA suggests:

Average path

Lago Tsan e bivacco

  • Elevation gain : 647 m
  • Travel time: 3h30
  • Signposting: 1-2-3-4-5-9

What to see:


Easy trails: routes that present no major technical difficulties or too challenging slopes. They can be covered in full or in small sections, allowing in both cases to come into contact with unspoilt nature, discovering its pace and balance …

Medium difficult trails: routes that can be covered in a day, varying considerably in terms of height differences and technical difficulty; the benefit is in being able to reach wildlife destinations of great impact.

Long trails: excursions lasting several days which provide for stopover places and catering along the route.

cartina High-altitude calcareous environments around Lake Tsan

SIC SIC IT1205081

Municipality: Torgnon, Nus

Surface: 453 ha

Altitude: 2.300 ÷ 3.009 m s.l.m.

Responsible forest station:
Antey-Saint-André, Nus

VIVA recommends the premises belonging to the network “Saveurs du Val d’Aoste

Saveurs du Val d'Aoste

discover the surroundings