If the fortification body built in Briançon at the end of the 17th century well controlled the outlet of Montgenèvre, it remained dominated by dangerous heights to the north, east, and south-east. The construction of the Fort des Salettes provided a solution to the northeast, as did the forts of Têtes and Randouillet to the south-east. These defensive works initiated a classic process of escalation of mountain fortification.