1. 1916, soldiers stationed in the Cathedral Redoubt, another building in the fortress complex on Cathedral Island. Notice the stark and cramped interior resembling the Lock’s lower level. From the collection of Przemysław Maćkowiak.

2. Drill on the main square in Fort Winiary, the central part of Poznań Fortress. From the collection of Przemysław Maćkowiak.

3. After lowering the bars in the window, soldiers could fire rifles in the direction of the Cybina River. Photo from Poznań Heritage Centre’s archive.

4. Canons by the windows were secured to iron rings in order to protect solders from the effects of the recoil after firing. The rings under the existing windows as well as under the windows which had been bricked in, survived. Similar rings, used for reloading canons, can be seen under the ceiling. Photo by Łukasz Gdak.

5. An earth bank and a decorative frieze on the façade – the building of the Cathedral Lock combined military functionality with beauty. Photo by Łukasz Gdak.