How to reach the high-mountain Tunnel des Inversens in Savoie?
Tunnel des Inversens is a high-altitude mountain tunnel at an elevation of 2,310 meters (7,578 ft) above sea level, located in the Savoie department within the Auvergne-Rhône-Alpes region of France. Situated near the base of the Roche de Mio peak, the unpaved single-lane service track leading to the structure serves as a maintenance passage inside the La Plagne ski resort layout.
| Road facts: Tunnel des Inversens | |
|---|---|
| Location | La Plagne, Savoie, France (Alps) |
| Elevation | 2,310 m (7,578 ft) |
| Tunnel Length | 136 m (446 ft) |
| Built | 1975 |
| Surface | Totally unpaved / Loose shale and rock bed |
What is the purpose of the Tunnel des Inversens track?
Constructed in 1975, the 136-meter (446 ft) rock tunnel serves a split purpose across the seasons. During the winter, the interior forms part of the blue ski run named "Le Tunnel," allowing skiers to cross from the Carroley mountain slope toward the Arc sector. The gallery dimensions are wide enough to accommodate heavy snow-grooming machines. Outside the ski season, from July to September, the snow melts away to reveal a raw, unpaved service track used by resort maintenance trucks to access the Lac des Inversens and the mechanical lift infrastructure at Roche de Mio.
What are the main hazards when driving Tunnel des Inversens?
The mountain route is an unmaintained single-track ledger reserved exclusively for authorized resort vehicles and emergency trucks. The steep approach roads consist of loose shale, deep ruts, and sharp slate shards that demand high-clearance 4x4 vehicles. The primary hazards inside the 136-meter gallery are the complete lack of artificial lighting and the permanent presence of thick ice patches on the rock floor well into late spring. The continuous steep inclines leading up from the La Plagne resort base put heavy thermal stress on vehicle cooling systems on the slow crawl up the mountain flanks.
Is the Tunnel des Inversens road open to the public?
Public transit is legally prohibited on this mountain track, which remains buried under deep snow drifts for over nine months of the year. During the brief summer window, the unpaved approach tracks suffer from constant erosion and rockfalls from the loose cliffs above. The single-lane path lacks steel guardrails or side walls, leaving wheels inches away from sheer rock drops next to the Lac des Inversens basin. Sudden alpine weather shifts regularly bring heavy cloudbursts and thick mountain fog that completely strips visibility from the narrow unshielded ledges.
Pic: Par Rémih — Travail personnel, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=147696036