The railway had great strategic advantages, as soldiers could now be transported from one place to another more quickly. This made it possible to travel further distances than before on foot. As the border of the kingdom began in the immediate vicinity of the railway station, this ensemble was also secured.

The entire Fort A complex was around five times larger than the "Reduit", the heart of the complex, which is still preserved today. After its military function, Fort A served as a military hospital and also as accommodation for soldiers. In 1878, the dismantling of the four outer defence rings on the site began, leaving only the Reduit standing, which was refurbished for use as an infirmary and accommodation. Large windows were cut into the outer wall for this purpose. The military use ended in 1918.

Because the ground was contaminated with metres of oil from the previous use, the site had to be renovated to a minimum. Original plans to set up the Prussian Museum here came to nothing. Fort A was used as temporary storage for larger agricultural equipment, which was stored here until it could be exhibited in the Minden Museum.

When the British left the city in 1994 and thus their barracks on Simeonsplatz, the buildings were earmarked for museum use. Fort A was left to its fate. For years, the ensemble remained in a "Sleeping Beauty sleep", then the Tucholsky Theatre took it over in 2008. The theatre people are firmly convinced that the ancient building has never been better used than it is today. They say that Fort A has simply been waiting for them for so long.