Built from 1893 to 1916, the Mutzig fortress was named "Feste Kaiser Wilhelm II" in 1895. It was the first German fortification to be made of concrete, entirely armored, ventilated and lit by electrical power. This prototype was an experimentation preliminary to the construction of the dispersed fortifications: ouvrages scattered on the terrain, dug underground and connected by underground galleries. It was the most powerful and largest fortification in the German Empire in 1914: it spanned 254 ha (636 acres), covered 40,000 square meters underground, with 22 artillery turrets& Its exceptional preservation and the excellent rehabilitation work and outfitting as a museum have contributed to make it a memorial and one of the best sites in Alsace for research into military architecture, technology and history. The visit is varied: infantry casemates, batteries of armored artillery, armored observation turrets, machine gun pillboxes, firing trenches& Numerous authentic objects and pieces of equipment can still be seen: the generating plant, the bakery, the kitchens, the wells, the men's sleeping quarters with their bunks, the surgery, the hospital, the toilets& Every year, an exhibition is organized on a historical or artistic topic :collections of French and German military headgear and paintings of the fortified belt around Strasbourg were the themes for 2002. Wear warm clothes.