Fort de l’Aisne, or in full Groupe Fortifié l’Aisne, was originally built as Feste Wagner by the Germans between 1904 and 1910. It was the last fort to be built in masonry, thereafter concrete became the preferred material.
The fort became French property after the boundary adjustments that followed World War I. It forms part of the second fortified belt around Metz and in particular protected the Seille Valley. Armaments included three batteries; of 15cm howitzers, 15cm long range artillery and of 10cm cannons. The fortified blocks are connected with extensive underground passages.
The fort was equipped with modern facilities for the garrison of over 1,000 men. These included central heating, running water, flush toilets electricity and telephones. In World War I the fort made some contribution to barrages on the front line but was not attacked. In World War II, part of the fort was converted into an underground munitions factory. It finally came under attack by aerial bombardment, followed by artillery assault by the USA in October and November 1944.
Today the fort is open on selected summer weekends by a local group with open dates publicised on their [website]{https://le-fort-wagner.com/la-visite/}