Heavy water infiltration required the provision of more extensive drainage work than originally planned.

[4] The blocks are linked by deep underground galleries, which also provide space for barracks, utilities and ammunition storage.

[5] In addition to the combat blocks, a detached casemate is near Denting: The 1940 manning of the ouvrage under the command of Captain Coste comprised 127 men and 2 officers of the 161st Fortress Infantry Regiment.

[9] The Casernement de Boulay provided peacetime above-ground barracks and support services to Denting and other positions in the area.

After the Second World War it became part of the Mòle de Boulay, a strongpoint in the northeastern defenses against Soviet attack.