This grid of passages, forming an energy self-sufficient shelter, offered protection for 3000 people.
One of the essential human drives that shapes our behaviour so as to ensure survival in the face of danger is the instinct for self-preservation. From the dawn of human history, humans have sought shelter against the malignant fates, searching out places in which they felt safe and that offered protection against a multiplicity of natural and societal threats.
The twentieth century, distinguished by its unprecedented scientific and technological development, introduced a new term to the strategy of war. With the onset of ‘weapons of mass destruction’ and development of the aviation industry, protecting civilian populations meant focusing on building anti-aircraft – and later fallout – shelters. In Brno, one such complex, buried beneath Petrov, was given the name ‘Denis’. It is located inside the rock massif of Petrov Hill and stretches for the most part below the area occupied by the Capuchin Gardens.
The Denis Shelter comprises a system of passages, intersecting at right angles, whose plan forms a rectangle approximately 85 x 60 m, with several entrances and an array of emergency exits. The arched corridors, cut into the rock and subsequently lined with brickwork, have a median size of about 3 x 3 m, and their total distance, combined with escape routes, comes to about 900 m. In the event of a nuclear attack, it would have been possible to survive inside the shelter for up to 4 days. In terms of water, electricity and a breathable air mixture, the shelter was self-sufficient, especially when ample stocks and rations had been stored away. These cramped spaces could have provided refuge for up to 3000 inhabitants. The only psychological support inside the passages was a public address system, broadcasting through a wired network.
Today, its long and empty corridors serve only as a depository for masonry fragments of King’s Chapel (Královská kaple), which once stood on the corner of Veselá Street and Dominican Square.