Facing the Vercors foothills, the fort was built on the Rocher de Comboire between 1882 and 1885, in response to the need to secure the border after the creation of the Kingdom of Italy in 1870. Overlooking the Drac valley and the south of the Grenoble conurbation, the fort's cannon fire prevented access to the Grenoble basin via the Drac valley and the road coming from the south. Essentially, the fort consists of a very long two-storey building with adjoining alveoli, housing the premises required for the fort's self-sufficient survival for 3 months. Doors and arcades are adorned with molded cement cornices. Other buildings are surrounded by deep, wide ditches whose sides are protected by small works called "caponnières".
The Rocher de Comboire on which it is built is a limestone massif with numerous galleries dug into its flanks to extract cement stone. Initially quarried by Société des ciments de la Porte de France, then by Vicat Cements, these quarries were used as raw materials for the construction of the fort.
The building has been awarded the "Patrimoine en Isère" (Heritage in Isère) label, recognizing the quality of the heritage of a building of departmental interest.