The Alpine Wall (Vallo Alpino) was an Italian system of fortifications along the 1,851 km (1,150 mi) of Italy's northern frontier.

Built in the years leading up to World War II at the direction of Italian dictator Benito Mussolini, the defensive line faced France, Switzerland, Austria, and Yugoslavia.

Due to the rugged nature of the Alpine frontier, defences were confined to passes and observation posts in accessible locations.

Three zones were designated at increasing distances from the frontier: Three types of fortifications were provided: The work, which was carried out in secrecy using Italian labor, was a significant economic burden, resulting in 208 installations with 647 machine guns and fifty artillery pieces.

[2] In addition, some Alpine Wall fortifications were used defensively by Italian and German forces during the Second Battle of the Alps in 1944.

The 1947 Paris Peace Treaty forbade the construction or expansion of fortifications within twenty kilometers of the border.

However, with Italy's membership in NATO, construction began on a new defensive line from Austria to the Adriatic along the Yugoslavian border along the Natisone and Tagliamento rivers.

The new line used tank turrets in a manner similar to German defences during the previous conflict, allowing 360-degree traverse and a high rate of fire.

Underground galleries connected the combat blocks and their support areas, such as the utility rooms, barracks, storage and command centres, with the main entry farthest to the rear.