Mont Blanc Tunnel

The Mont Blanc Tunnel is a highway tunnel in Europe, under the Mont Blanc mountain in the Alps. It links Chamonix, Haute-Savoie, France with Courmayeur, Aosta Valley, Italy, via European route E25. The passageway is one of the major trans-Alpine transport routes, particularly for Italy, which relies on this tunnel for transporting as much as one-third of its freight to northern Europe. It reduces the route from France to Turin by 50km and to Milan by 100km. Northeast of Mont Blanc's summit, the tunnel is about 15km southwest of the tripoint with Switzerland, near Mont Dolent.Begun in 1957 and completed in 1965, the tunnel is 11.611km in length, 8.6m in width, and 4.35m in height. The passageway is not horizontal, but in a slightly inverted "V", which assists ventilation. The entrance elevation on the French side is 1274m and 1381m in Italy, with a maximum of 1395m near the center, a maximum difference of 121m. The tunnel consists of a single gallery with a two-lane dual direction road. At the time of its construction, it tripled the length of any existing highway tunnel.