Cadorna Line

Its purpose was to protect the Po Valley and its main industrial centres from an attack by France, Germany or Austria-Hungary violating Swiss neutrality.

[1][2] In 1862, shortly after the birth of the Kingdom of Italy, the Army General Staff first considered the need to fortify its borders with Switzerland to prevent an invasion through the Alpine passes - the Great St Bernard, the Simplon, the Gotthard, the Spluga, the Maloja, the Bernina, the Stelvio and the Tonale.

However, in 1882 the General Staff Committee declared its opposition to the idea, considering an Austrian violation of Swiss territory unlikely, and a German attack unrealistic.

Nonetheless, work on the projects resumed, and carried on haltingly until 1911, when the State Defense Office brought forward a scheme along the Bergamasque Alps and the Ticino salient.

General it:Carlo Porro warned Chief of Staff Luigi Cadorna that an invasion of Lombardy by the Central Powers, through neutral Switzerland, could lead to an attack on the area of Milan and thus on the heartland of Italian industrial production.

[4] It included roads, mule tracks, paths, trenches, artillery positions, observatories, field hospitals, command centers and logistics structures, all built at high altitudes from 600 to over 2,000 meters.

Toce-Verbano: (Simplon Pass to Lake Maggiore) The Ornavasso barrier was strengthened by providing a final retreat line at the Candoglia quarries in order to take advantage of the natural defense offered by the mountains of the Val Grande.

The Colico barrage was considered insufficient since its location, at the level of the lake, could allow the enemy to fight back from higher ground with artillery stationed on the nearby hills.

The entrenchments were a succession of broken lines, often with sharp angles to ensure the greatest possible protection against the explosion of grenades, and at regular intervals they presented "bell" niches for the shelter of sentries in case of bad weather.

The fortified system was entrusted to the commander of the 5th Army from Varese, Lt. Gen. it:Ettore Mambretti who had the task of protecting the left flank of the Italian defensive front.

Due to the lack of troops, which were almost entirely employed at the front, the posts and barriers were built in more rearward positions, in order to exploit the terrain.

“Plan B” involved an offensive "leap" up to the passes of Monte Ceneri and Bernina and occupying the northern border ridges of the Adda river.

The Cadorna Line was briefly the focus of attention in 1938, when Mussolini thought about invading Switzerland,[3]: 19 [12] perhaps to flex his muscles with the Germans who had recently annexed Austria.

The only war action on the line was on November 13, 1943, when the first battle of the resistance took place in the bunkers of San Martino in Valcuvia, when fascist government forces defeated a group of partisans led by Colonel Carlo Croce.