​​​​​ ​​


The borderline in 1915 was that unfavorable line established by the Treaty of Vienna in 1866. That line had the shape of an “S” set horizontally on the Veneto Alps, so that Austria could enter the Italian territory on the west, in a large wedge with the base along the Stelvio-Cima Vanscuro line (160 km) and the vertex on the Adige, up to ​Peri (160 km from the Brenner and less than 30 km from Verona).

This large wedge represented a constant and serious threat for the back of the Italian forces on the east, but it was reduced by the insufficient potentiality of roads and railways from Austria.

The other part of the “S” was the Italian salient of the Isonzo river, not very dangerous for Austria because it ended against the first spurs before the great mountain chain of Alps: Giulie and the first carsick step.

The whole operational area could be divided into two zones following the direction of the parallels: the mountainous zone to the north and the flat zone to the south.

Among the rivers that crossed the plateau, the Piave was the best for a rapid economic efficient defense. The area that was the most suitable for the employment of big units was the Isonzo area because the northern part of the operational area was mountainous ​and its few cracks had been barred by both enemies through permanent defensive walls.

Moreov​er the road and railway communication lines, with a sufficient potentiality in strategic offensive actions, went only to that sector.