From the outset of the war, some countries boycotted Pilsner Urquell as a German product, therefore exports were directed exclusively to Germany. The brewery produced “weak war beer” and survived only because it supplied beer to the workers at the Škoda Works.

During the war, protective constructions called “Splitterschutzzelle” (observation towers) or “Einmannbunker” (one man bunker) were built at each of these breweries. As simple precast concrete cylinders with narrow openings, they were probably among the first prefabricated fortified structures. They did not provide adequate shelter during air raids but were used as observation towers for posted patrols.

Towards the end of the war, Pilsen experienced bombing and both breweries were extensively damaged while the Gambrinus was almost completely destroyed. After the bombing was over, fire patrols used these observation towers to monitor the results of the air raid and to help to locate unexploded bombs.