The Fort de Koenigsmacker (Koenigsmaker, Königsmachern or Kœnigsmacker) is a fortification located to the northeast of Thionville in the Moselle department of France. It was built by Germany next to the town of the same name in the early 20th century after the annexation of the Moselle following the Franco-Prussian War. The Fort de Koenigsmacker was part of the Moselstellung, a group of eleven fortresses surrounding Thionville and Metz to guard against the possibility of a French attack aimed at regaining Alsace and Lorraine, with construction taking place between 1908 and 1914. The fortification system incorporated new principles of defensive construction to deal with advances in artillery. Later forts, such as Koenigsmacker, embodied innovative design concepts such as dispersal and conce