After 1866, when Veneto became part of the Kingdom of Italy, the border with Austria was located between Veneto and Trentino Alto Adige, placing the city of Verona more or less on the boundary of the kingdom. The area was therefore militarised, and Lessinia was transformed as a result. Against this historical backdrop, the Forte Monte Tesoro was built between the Valle di Prun and the Valpantena from 1905 to 1911; it has recently been restored and redeveloped. Based on a Belgian model and designed using new techniques to defend against increasingly powerful and precise explosive weapons, the fort in turn became a model replicated by Italy's military engineers along the entire Alpine border. It was the first fort of its time built with local Lugo stone and on a concrete base. It is divided into several levels: a ground floor plus two other floors, all surrounded by a moat that cordoned off the whole fort area. Inside, tunnels and passages lead to what were once the rooms where the soldiers slept, ate and lived. Some of the tunnels lead to the outer trench, where there were three retractable machine gun turrets. The terrace on the upper level of the fort had (and still has) a breathtaking view of Lessinia, and was once used as an observatory. Finally, on the north side of the access road we find the barracks, well sheltered by the rock. However, since the fort was not on the front line of the Great War in this region, it was disarmed and was instead used as an ammunition depot by the Italian Army until fairly recently. Today, it is used occasionally for exhibitions or for certain special conferences.
Forte San Briccio (1885), between the Mezzane and Marcellise valleys; Forte Castelletto (1885), of which scant ruins remain following an explosion at the end of the Second World War; Forte Masua (1883–84), guarding Val d'Adige; and Forte Santa Viola, defending the Valpantena and the Val Squaranto: these are just a few of the forts that formed Lessinia's defensive line together with Monte Tesoro. Not forgetting the trenches of Malga Pidocchio (in Erbezzo) and Valòn (in Malga San Giorgio), which were also part of this system.