Italian fortifications on the Austro-Hungarian border

This frontier was difficult to defend, since Austria-Hungary held the higher ground, and an invasion would immediately threaten the industrial and agricultural heartlands of the Po valley.

From 1870 a second wave of building took place, in which fortifications were built with much thicker walls and lower profiles, responding to advances in artillery technology.

[8] Because Italy was in a hurry to complete its key fortifications before war started, the newest forts - Campolongo and Verena in particular - had not been well built.

[9]: 165  [10]: 144–5 At the start of the First World War, Italian fortifications were organised into defensive groups called ‘sbarramenti’ (“barriers”).

Bringing up additional artillery, the Italians were able to virtually destroy Fort Verle, but were still unable to take it with their infantry because of the maze of trenches and barbed wire that surrounded it.

[21] In early November 1917 Austrian and German forces reached the Piave and were confronted by the Monte Grappa massif that extends from the river to the Brenta-Cismon barrier in the west.

[22] At the start of the war in 1915 Monte Grappa was unfortified, but General Cadorna anticipated its future importance and in the autumn of 1916 ordered the construction of extensive fortifications to turn it into a stronghold.

This was to include a major defensive structure tunnelled into the summit as well as batteries and smaller outworks to provide crossfire against an enemy advancing from any direction on the slopes.

[23] On 7 October 1917 Cadorna inspected progress in building the fortifications, which were mainly facing towards the west, and ordered that the north and east he fortified too, in case there was a need to fall back from the Isonzo.

[22] The Italian High Command had 50 battalions on Monte Grappa – around 50,000 men, supported by a French contingent from December, and fought them off.