Aye, as stated there were 3 of these towers in Berlin, each with reinforced concrete walls 8ft think. The towers were 13 storey's high with 5 floors of these below ground. During the last days of the Battle of Berlin many treasures were moved to these towers for safer protection. Each Flak tower could hold up to 15000 people, which shows the immensity of the buildings. On top were the Flak guns which were 128mm in size, not sure of how many were placed on top of the towers thou.