Ouvrage Rochonvillers is one of the largest of the Maginot Line fortifications. Located above the town of Rochonvillers in the French region of Lorraine, the gros ouvrage or large work was fully equipped and occupied in 1935 as part of the Fortified Sector of Thionville in the Moselle. It is located between the petit ouvrage d'Aumetz and the gros ouvrage Molvange, facing the border between Luxembourg and France with nine combat blocks. Rochonvillers saw little action during World War II, but due to its size it was repaired and retained in service after the war. During the Cold War it found a new use as a hardened military command center, first for NATO and then for the French Army.