After the outbreak of the Great War in July 1914 (the name “First World War” only came into widespread use after 1939), Bratislava became a strategic location. It lay on the expected route of any Imperial Russian advance towards Vienna and formed the last major barrier before the capital. From there, they could have reached the central part of Hungary, as well as Moravia and the Austrian part of the monarchy, without encountering any major resistance. The fortifications were intended to protect the bridge, stop Imperial Russian troops from crossing the Danube, and keep Vienna from being encircled. The overall design for the field fortification of Bratislava was prepared by Army General František Škvor (who was a major at the time). Detailed plans were drawn up for the individual pockets of resistance, the types of shelters, the various gun positions, the quantity and types of weapons, and the required labour and materials. The defensive line around the city was almost 50 km long and consisted of five sectors. The selected locations offered excellent conditions for observation and for protecting the city in all directions with long-range artillery fire. The sectors consisted of a system of trenches, fortified artillery positions, barbed-wire obstacles, and permanent fortification structures used to store ammunition and shelter the artillerymen themselves. Depending on the conditions at each site, the shelters were built either as “Kavernen” or as “Unterstände”. Kavernen were designed mainly for the hilly terrain in the northern and western parts of the city, while Unterstände were used mainly on the flatter ground on the eastern and southern edges of Bratislava. Kavernen were either driven into the rock using mining techniques, with the wall lining concreted afterwards, or built in an open excavation, with ceilings covered by iron girders and then covered with earth. It was rare for Kavernen driven into the rock to be concreted along their entire length (the Kamzík and Rösslerov lom sites are examples of this). For the most part, only the entrance area was concreted, while the rest of the structure remained as it had been cut out of the rock. In terms of size, Kavernen can be divided into small and large types. Small Kavernen have one entrance, an angled entry corridor, and one room. Large Kavernen have multiple entrances and rooms. Kavernen of this kind have so far been found only at the Sitina and Kamzík sites. Kamzík, structurally complete with four entrances and two storeys, is a unique example of this type. Unterstände were built either entirely of concrete or partly of masonry walls with concrete ceilings, and were fully sunk below ground level. They had a rectangular ground plan with a single covered entrance. These block-like structures measured approximately 6 x 18 m and had side recesses in the rear wall. They were set into the ground, with the entrance covered, and were built either entirely of concrete or in brick-and-concrete form. The Kavernen and Unterstände were maintained until the end of the Great War in 1918. Since Bratislava saw no fighting, the entire line remained undamaged after the war. After the establishment of Czechoslovakia, it was left unused and gradually fell into oblivion. Some of these structures were used by the German army in 1942–45 as support facilities for artillery batteries in exposed positions. Today, approximately 75% of the structures from the original line have survived and been recorded. These are mainly Kavernen and Unterstände in the western, north-western, and northern parts of the city, where they remain almost intact. The eastern and southern parts of the city (Nové Mesto, Ružinov, and Petržalka) underwent major transformation in the 1960s and 1970s, and many structures were destroyed during the construction of housing estates and transport infrastructure. Most of the surviving structures have been left in their original condition, with no maintenance or safety measures in place. They are freely accessible, but the entrances are often partially filled in. Emergency exits, hidden beneath branches and leaves, may pose a fall risk. Anyone exploring these structures on their own should exercise particular caution. Of the total number of surviving structures, four are managed by OZ Bunkre (three Kavernen and one Unterstand); they have been restored and are open to the public.
First World War
