Federal Fortress Ulm-Nebenwerk Oberer Eselsberg

The Federal Fortress of Ulm, which includes the Oberer Eselsberg Outwork, was constructed between 1842 and 1859. It was one of the major projects of the German Confederation after Napoleon's defeat in 1815, aimed at ensuring internal security. The construction was designed and overseen by the Prussian fortress architect Moritz Karl Ernst von Prittwitz und Gaffron. On the Bavarian side, Major Theodor Ritter von Hildebrandt took over leadership from 1843. Up to 10,000 workers were involved in its construction. The fortress was designed to accommodate 5,000 soldiers in peacetime, with capacity for up to 20,000 soldiers in case of war.