On the road cutting through Gotthard Pass, hidden into the mountains bowels, there is the strongest Swiss war-citadel: the Sasso.

Operative until few years ago, the Sasso is an intricate network of tunnels carved into stone: it is the last Swiss stronghold against the Fascist Italy between 1940 and 1945.

Each tunnel of the Sasso, the deepest 3.5 kilometer-long, leads to underground barracks, head quarters and outdoor shooting positions, connected by ladders and even underground railways.

In the core of the citadel, kilometer-long pipes bring water and air and electricity for supporting life of soldiers and workers in the barracks: a total of 240 operatives was living here.

The Swiss General Guisan ordered the construction of Sasso in 1940. Together with two additional fortresses at the West and East corners of Switzerland, Sasso was built as last resistance against the German Nazis and the Italian Fascists.

From its control room, Sasso was ready to shoot 50 cm (!) calibers to collapse two mountain passes, thus to stop enemy soldiers from crossing the Alps. Mountains, in the mind of General Guisan, would have been the last, desperate refuge of the Swiss folk in case of invasion of the flat lands.

Nowadays the cannons are not anymore operative … but they still watch down the Southern valleys, waiting for the enemy to come.