The Fort of Duffel or the 'Railway Fort' was built in 1886. It was part of a larger fortification belt around Antwerp comparable to the Walem Fort and the ones of Sint-Katelijne-Waver and Lier. During the 19th century Antwerp was the national 'reduit' or refuge of Belgium.
Belgium as a young and neutral country was stuck in between nationalist superpowers and when the war broke out its government and the army were to withdraw and remain in Antwerp to offer resistance and await assistance from the allies.
In order to become a fortified city Antwerp was expanded and now surrounded by great walls and a fortification belt made up of eight forts located at only several kilometres away from the walls. After the French- German war (1870-1871) the government decided that an additional outer layer was needed to guarantee optimum protection of the city. To begin with 21 extra forts were constructed and spread out over a 95 kilometres long arch around Antwerp. The Fort of Duffel was one of these and its specific purpose was to protect the main railway between Antwerp and Brussels.
In 1886 an entrenchment, canal and walls of earth were built. In 1894 the Railway Fort was renovated into an armoured fort with reinforced concrete arches.