The redoubt was provided with a drawbridge and impressive walls. The casemates were cut from rock and accessed by underground galleries. Renovations in the 1930s provided concrete reinforcement. The redoubt was kept as military property until the 21st century, but has suffered considerable deterioration. It is now community property and may not be accessed. The Maginot "ouvrage" extended under the barracks and redoubt of Fort Sapey. Entered from the west, the galleries connected to the old "abris" of the barracks, emerging at combat blocks under the walls for the redoubt on the east side. The proposed 145mm turret was to be built in the area of the barracks, near the underground utility plant. A 145mm gun turret was planned but never installed. The 75mm guns of Sapey "Fréjus" battery fired on Italian troops in the vicinity La Roue on 20 June 1940. The next day the battery fired on the Vallée-Étroite. "Fréjus" was joined by Battery "Maurienne" on the 22nd, firing on Italian forces in the vicinity of Bramans. The next day the "ouvrage" fired toward Planey. Further bombardments followed on the 24th and 25th, ceasing with the armistice of the 25th. Fire direction as provided by Ouvrage Saint-Antoine. A total of 1428 shots were fired by "Maurienne" and 981 by "Fréjus." After the 1940 armistice, Italian forces occupied the Alpine "ouvrages" and disarmed them. In August 1943, southern France was occupied by the German 19th Army, which took over many of the Alpine positions that had been occupied by the Italians until Italy's withdrawal from the war in September 1943. In 1944, Sapey was recaptured relatively easily on 13 September. Sapey had suffered little damage during the war, apart from the destruction of its aerial tram, and by the end of 1944 was partly repaired and placed into service. Immediately after the war, the Maurienne region was regarded as an area of medium priority for restoration and reuse by the military. By the 1950s the positions in the Southeast of France were restored and operational again. However, by 1960, with France's acquisition of nuclear weapons, the cost and effectiveness of the Maginot system was called into question. Between 1964 and 1971 nearly all of the Maginot fortifications were deactivated.