Forest Management for Protection
From the 15th century onwards, the exploitation of the forest intensified and became disorderly, depleting resources to such an extent that regeneration for future generations was no longer assured. More space was required for meadows and fields, more timber for lime furnaces, mining, ovens, and an increasing demand for beams and shingles to roof homes.
The first regulations were introduced to rationalise forest use and safeguard these vital resources, laying the groundwork for today’s naturalistic forestry in the Aosta Valley, which recognises the forest’s many functions.
In 1716, the Conseil des Commis—an institution dating back to 1536 that governed the Aosta Valley for two centuries—was informed that avalanches along the road to the Little St Bernard Pass had caused numerous fatalities due to extensive forest clearing. A fine of 10 lire was imposed. The residents of Pré-Saint-Didier were particularly affected, having no alternative forests to turn to.
After years of protests and petitions, the issue was revisited, and in 1726 specific areas were designated for logging. Mutual accusations of illegal cutting heightened tensions, but the path was set: forests were officially recognised as essential, protecting villages and roads from avalanches and landslides.

The Stone Pine of Chavanne Valley
The Chavanne Valley, branching off to the right just before the hamlet of Pont Serrand on the way to the Little St Bernard Pass, is now devoid of trees. Yet its slopes are still known as “Les arolles,” the local patois term for the Stone Pine.
It is easy to imagine these steep slopes once densely carpeted with this cold-resistant species, with avalanches frequently sweeping through, leaving behind stumps. The discovery of one such stump has allowed significant dendrochronological studies, providing invaluable climatic information from its long life. Laboratory analysis dated the tree’s death between 1530 and 1670, with 592 growth rings counted.
This Stone Pine likely grew within a forest gradually thinned by glacial pulses, which exposed and strengthened it—once between the ages of 185 and 280 years, and again in its final 30–40 years. At 578 years old, it faced its greatest challenge: a sharp temperature decline weakened the tree. Though its roots clung steadfastly to the soil, wild waters and avalanches eventually uprooted it. Today, the stump is preserved at the Aosta Valley Regional Museum of Natural Sciences.

Forest for Everyone
The forests that remain today represent only a fraction of what once covered the land. Human activity, including the creation of ski slopes, has significantly reduced forested areas.
The surviving forests are now partly managed at a regional level, regulating use and mitigating the effects of abandonment. Today, forests serve broader functions—not merely economic, protective, or productive, but also scenic and recreational—while timber production has become a marginal activity.
Since the late 1970s, forest management in the Aosta Valley has followed principles of naturalistic forestry, aiming to cultivate a multi-aged, mixed-species woodland, thereby restoring the natural stability once sacrificed to human needs.
Selective logging, undertaken by specialised forestry teams, brings considerable ecological benefits by enhancing hydrogeological protection, promoting health and hygiene, conserving biodiversity, preserving landscape value, providing recreational opportunities, and ensuring the production of high-quality timber.
The forest in the heart of La Thuile now offers a cool, refreshing environment for walking, engaging with mountain flora and fauna, exercising along fitness paths, playing in the marmot corner, dining at tables and grills, and discovering the surrounding natural world.
Venturing further, the woods extend towards Col San Carlo. The hamlet of Buic, whose name derives from “Bouque,” meaning “at the foot of the forest,” offers walks that reveal traces of La Thuile’s mining heritage, older military trenches, and waterfalls framed by lush greenery at the foot of the Ruitor Glacier—a true infinity trekking experience!

The “Prince Tommaso” Entrenchments (17th–18th Century)
In response to French expansionist ambitions, Charles Emmanuel I of Savoy — known as the Great — was Duke of Savoy and ruler of the Savoyard state from 1580 to 1630, and was compelled to devise the first defensive plan for the border regions, including the Aosta Valley. Early strategic efforts centred on the heights behind La Thuile, particularly the Mont du Parc ridge, which offered near-complete visual control over the route ascending from the pass.
During this period, Prince Thomas of Savoy–Carignano — charged by his father with the defence of the borders, as attested in a letter dated 31 May 1630 — emphasised the necessity of constructing fortifications at the Little St Bernard Pass. It is at this time that references first appear to the Sardinian Retranchements, also known as the Entrenchments of Prince Tommaso.
The French, however, were not idle. In the Haute-Tarentaise, Louis XIII, together with Cardinal Richelieu and his marshals, devised and began erecting a far more formidable defensive system centred on Fort Saint-Maurice — a bastioned stronghold of earthworks, garrisoned by 3,000 men, near what is now Bourg-Saint-Maurice.
Nearly sixty years later, the threat posed by Louis XIV of France during the Nine Years’ War compelled Victor Amadeus II — also known as Victor Amadeus Francis of Savoy, ruler of the Savoyard state from 1675 to 1730, King of Sicily from 1713 to 1720, and King of Sardinia from 1720 to 1730 — to mobilise regiments and plan the defence of the Duchy of Aosta’s western frontier with the Tarentaise. In the first half of the eighteenth century, surveys and expert reports recommended reinforcing the entrenchments and defensive structures, which were deemed insufficient both at the high altitude of the pass and further down the valley, where a secondary defensive line was considered essential.
One consequence of these fortification works was the interruption of the traditional Roman road, which was replaced by a new route that remained in use until the completion of the Route Nationale 90 in 1866.
Typically, these entrenchments consisted of a system of sheltered walkways along the ridge, including a guardhouse, a musketry curtain, and a long semi-subterranean building with a single-pitched roof built into the slope.
Towards Pétosan lay one of the most strategically important positions for military engineers from the mid-seventeenth century onwards. From here, a direct line of sight was maintained over the road from the Little St Bernard Pass, aiding the defence of the La Thuile basin in concert with the high-altitude fortifications at Folliex and the imposing fortified complex of the Col de la Croix. Defensive control of the valley floor itself was ensured by multiple entrenchment systems, clearly marked on eighteenth-century military maps, although no visible traces remain today. Further east, the trenches at Folliex, situated below the fort at Plan Praz, were designed to thwart any potential enemy advance across the Rutor Glacier.
The defensive system fell into disuse following military events in late April 1794 and again the following year, culminating in the occupation of the La Thuile area by the Army of the Alps, commanded by General Kellermann. The fortifications throughout the sector — with the exception of those at Foullié and the Col de la Croix — were decommissioned in 1797.