The Vienna anti-aircraft towers are six high defence and protection structures made from reinforced concrete. They were built in the years 1942 until 1945 as air-raid protection and had rigged up anti-aircraft guns and fire control devices. The architect of the flak towers was Friedrich Tamms (1904-1980).
The Vienna system of anti-aircraft towers consists of six buildings, three turrets, each of them with one fire control tower. The three bunker pairs are arranged in a triangle, whose centre approximates St. Stephen’s Cathedral. The towers are different in height, yet each of the upper platforms is at the exact same sea level, enabling a complete coordination of air raid defences. The maximum deployable radius of the four main guns (12.8cm twin) of each tower under ideal conditions amounted to 20km. The smaller platforms of the gun and fire control towers were designated for 2cm anti-aircraft guns, but they were never used in Vienna. Apart from the military forces the flak towers in Vienna served as provisional hospitals, housed radio stations and partly strategic technical undertakings. They also provided a large facility of air-raid shelters for the population. After the war, the Red Army attempted demolition of the gun tower Augarten, however, removal of the towers failed due to the proximity of residential buildings. Nowadays, a removal of the towers would be easy, but in the meantime all six of the buildings are under a law protecting monuments. Yet the only decree in existence is that for the two flak towers in the Augarten dating from 5 April 2000 (GZ 39.086/2/2000). Today, the towers are to some extent in the possession of the city of Vienna and partly a property of the Republic of Austria. There have been several attempts to reconstruct and utilize the flak towers. Ideas range from a warehouse for back-ups of important data, to a coffee house or a hotel.
Adolf Hitler ordered the construction of flak towers in Vienna on 9 September 1942 when the battles of the Second World War started to encroach on Vienna. What the Air Force Command had in mind were building grounds in the Schmelz (Vienna), the Prater and Floridsdorf. But Hitler rejected these places, since the city centre would not have been sufficiently protected. After discussions with Reichsstatthalter (imperial governor) Baldur von Schirach, the definitive positions were determined. Initially, however, instead of the Augarten, the Rossauer Kaserne was under debate. It was crucial in the selection of locations that the land was readily available and there were prospects for rail connections. The plan envisaged that after the victorious end of the war, the flak towers would be clad in marble and dedicated as a memorial to German soldiers killed in action. Friedrich Tamms was responsible for the planning of all the flak towers. In Vienna he was represented by Anton Ruschitzka and the position of construction management was held by Franz Fuhrmann of the Viennese building authority. Military Leader Major Wimberger, however, did not have operational staff available. The organisation Todt was in charge of the procurement of materials.
The companies Philipp Holzmann and Gottlieb Tesch were commissioned with the construction of the flak towers, while smaller businesses were involved through working groups. Since the availability of local employees continuously diminished due to enlistment, more and more prisoners of war, foreign and forced labourers were employed in the labour as the war continued. Cement was delivered for the main part from Mannersdorf am Leithagebirge and to a lesser extent from Rodaun. The gravel came from the quarries Padlesak in Felixdorf and Gustav Haager at Heidfeld by the Pressburger track, which was in the region of the present-day Vienna International Airport. Sand was delivered on vessels on the Danube Canal, for which the United Construction Supply Factory (Vereinigte Baustoffwerke AG) built sand silos in the area of the Weissengerberlonde. A connecting track of the tram system through the Drorygasse existed in that area since 1918. Although it was shut down in 1925, it was reconstructed in 1941 and extended by two tracks in the following year after the construction of another silo. For the waste material arising from the excavations of the foundations, a disposal site was laid out at the Kratochwjlestrasse (then Weissenbachstrasse) in the 22nd district, which likewise received a tram connection.