Until the occupation of Doberdò del Lago/Doberdob, the Austro-Hungarian Army held important gun positions on Mt. Colle Nero/Črni hrib. The 123rd Regiment of the Chieti Brigade conquered the hill in the Sixth Isonzo Battle (4–16 August 1916). Between 1916 and 1917, the Italians built a refuge on the hill and named it after Italian General Luigi Cadorna, who visited nearby positions on South Hill 208 (Quota 208 Sud/Varda) on 1 March 1917, and probably stayed overnight on Colle Nero. Since that day, this refuge has also been known as Casa Cadorna.
To reach Mt. Colle Nero/Črni hrib, drive to the parking lot of the Nature Reserve Gradina (Riserva Naturale Gradina), located in the municipality of Doberdò del Lago/Doberdob. From the Gradina Reception Center, take the CAI 77 trail towards Colle Nero‒Monte Castellazzo/Gradina.