Mont-Blanc Tunnel to close for 15 weeks: What are the alternatives?

The world’s second deepest tunnel will be closed for renovations.

Driving between France and Italy this year? You may be forced take a detour as the Mont-Blanc Tunnel, which links the two countries beneath the Alps, is closing for 15 weeks for renovation work.
Between 2 September and 16 December, a 600-metre stretch of the 11-kilometre tunnel will be completely reconstructed. During this time, the Tunnel du Mont-Blanc will be closed to traffic.
Alternative routes are available but they will likely add to your travel time. Here’s how to plan your Europe road trip around this autumn’s closure.
Opened in 1965, the Mont-Blanc highway tunnel links Chamonix in Haute Savoie, southeast France, with Courmayer in Aosta Valley, northwest Italy.
It is part of the north-south European route E25, which runs from the Hook of Holland down to the ferry crossing from Cagliari to Palermo in Sicily.
Lying 2,480 metres beneath the Aiguille du Midi summit, it is the world’s second deepest tunnel in operation after Switzerland’s Gotthard Base Tunnel.
Various closures have taken place throughout 2024 to allow for maintenance work, safety drills and renovation.
This autumn’s closure is scheduled for structural renovation work on the vault. It will be one of the first major European tunnels to undertake deep renovation work on its structure. 
Between 5pm on 2 September and 5pm on 16 December, different reconstruction technologies will be tested on two 300 metre stretches of the tunnel.
The most efficient and effective techniques could then be applied to an additional 600 metre section during another closure in 2025 – and further works along the tunnel’s entire length in the coming years.
During the Mont-Blanc Tunnel closure, it will still be possible to drive between France and Italy on different routes.
Although these may extend your journey time, they could save you money: the one-way toll for a car use to the Mont-Blanc tunnel is €51.50 while a return is €64.20.
Around 160 km south of the Mont-Blanc Tunnel, the Fréjus Tunnel connects Modane in France to Bardonecchia in Italy. It is slightly cheaper to use, with a one-way trip for cars costing €47 and a return €57. Heavy goods vehicles will be diverted to this route during the closure.
Toll payment subscriptions including the TMB card and Eurotoll cover both tunnels under the same pass. Multi-journey discount passes valid during the Mont-Blanc Tunnel closure will automatically be extended by four months.
Alternatively, the Tunnel du Grand-Saint-Bernard links Martigny in Valais, Switzerland, with Saint-Rhémy-en-Bosses in Italy’s Aosta Valley. The one-way toll for a car is €31.
Located further southwest, the Col du Petit-Saint-Bernard is a mountain pass linking Savoie in France with Aosta Valley. However, it could face closures due to heavy snow, so check the weather before planning your route.
To the north, the Col des Montets mountain pass, linking Chamonix with Vallorcine in France – on the border with Valais – is another route that could be hit by snow closures. 
The Tunnel des Montets, a single track railway tunnel that doubles as a road, can sometimes be used when the pass is closed but it is likely to face heavy traffic.
The scenic Mont Cenis pass between the Cottian Alps in France and the Graian Alps in Italy is typically open to traffic until November, when it closes for the winter season.
The Montgenèvre Pass connecting Briançon in France and Cesana Torinese in Italy is another option for road travel further south of the Tunnel du Mont-Blanc.