On the southern slope of the Soratte, a short distance from the town centre, is the military bunker built in 1937 by the military engineers of Rome on the initiative of Mussolini. It is a network of tunnels inside the mountain that extends for about 4 km in length and which - behind the cover of the Breda arms factory - instead constituted an air-raid shelter for the top management of the General Staff: to date one of the largest and impressive military engineering works in Europe.
When, after 8 September 1943, the German supreme command of the South was bombed in Frascati, Field Marshal Albert Kesselring, who was in charge of it, arranged to transfer its headquarters to Soratte. There it would remain almost undisturbed until early June 1944. The bunker also resisted the bombing of 12 May 1944 carried out by two flocks of allied B-17s, which had left specifically from Foggia to destroy it. The operation, which hit many houses in nearby Sant'Oreste, caused about a hundred victims among the 980 German soldiers in the town. To leave, however, the Wehrmacht troops waited for June 5, when British and American tanks entered Rome. Before leaving, they flooded the tunnels with petrol and set them on fire. To enter, the British had to wait for the fire to burn itself out five days later.
After the end of the war, the complex remained abandoned until 1967, when a fallout shelter was built under the aegis of NATO, which however was not completed and abandoned in 1972.