Mont Blanc Tunnel: length, tolls and the Chamonix-Courmayeur drive

11,611 m, or 11.6 km. Wikidata and Wikipedia give the value to the metre; ATMB rounds it on its information pages. The Italian portal sits higher than the French portal: a driver leaving France climbs for most of the crossing, then descends slightly towards Italy.

On 19 July 1965 for tourist traffic, three days after the official inauguration. Heavy goods vehicles were admitted only from 20 October 1965. Wikipedia puts the saving at about sixty kilometres on the journey between Chamonix-Mont-Blanc and Aosta, which until then depended on mountain passes closed for part of the year.

Two concessionaires, one per country. ATMB, Autoroutes et tunnel du Mont-Blanc, created in 1958 under the name STMB, runs the French side. The SITMB, Società Italiana per il Traforo del Monte Bianco, incorporated on 1 September 1957, runs the Italian side. The fire of 24 March 1999 killed 39 people and closed the tunnel for almost three years, until it reopened on 9 March 2002. The two companies then merged their operating and safety teams into a European economic interest grouping held in equal shares, the GEIE-TMB, headquartered in Courmayeur.

€55.50 one way in class 1 from France, €69.20 return. The price depends on the direction of entry, with Italy charging €56.40 and €70.40 for the same car.

ATMB announces 10 minutes for the crossing. Neither ATMB nor the SITMB publishes a door-to-door time between the two town centres. Beyond the tube, the journey depends on the access roads and above all on the wait at the toll. The barriers let in only one vehicle every 8 seconds, the time needed to set the regulation distance from the vehicle ahead, which caps the number of vehicles inside the tunnel at any one time. ATMB counts up to 7,800 families on Saturdays in July and August.

70 km/h maximum along the whole length, 50 km/h minimum, and 150 m between two moving vehicles. Blue lights line the wall and serve as a marker. ATMB asks drivers to keep two of them between their vehicle and the one ahead. Speed drops to 50 km/h at the French exit and 40 km/h at the Italian exit. When stopped, the minimum distance falls to 100 m. Any unjustified stop triggers a safety procedure.

ATMB writes on its works page: “There will be no long-term closure in 2026 for the renovation of the vault.” This pause is meant to let the French and Italian States review the outcome of the 2024 and 2025 works periods before settling the method for the five kilometres of vault still to be renovated. The 2023 campaign shows how long a long stoppage lasts: nine weeks of total closure, from Monday 16 October 2023 at 8:30 am to Monday 18 December 2023 at 10 pm, with reopening finally brought forward to Friday 15 December 2023 at 4 pm. ATMB does not publish the dates of the 2024 and 2025 campaigns on this page. Night closures for maintenance continue, on a calendar published in advance.

In the event of a breakdown, ATMB asks drivers to reach an emergency stopping bay, located on the right every 600 m, or failing that to park as close to the kerb as possible, switch off the engine, turn on the hazard lights and alert the control room from an SOS niche. In the event of a fire, or a breakdown with smoke or vapour: stop the vehicle, switch off the engine, turn on the hazard lights, then quickly make for a secure green shelter marked by flashing lamps. The SOS niches, every 100 m, connect to the control room and contain fire extinguishers. The 37 shelters, every 300 m, have a video phone and open onto an evacuation corridor beneath the roadway. ATMB specifies that the niches are not designed to protect people from the effects of a fire.