Well, guess you know the basics but ill just start writing and if you want to know anything in particular or i left out anything, just ask
In Vienna you got 3 pairs or 2 towers. The G-Turm or Gefechtsturm was the Tower with the guns and the L-Turm or Leitturm with Radar and communications equipment for acquiring targets. They where separated so you would save space on the roof for more guns because of the huge radar dishes and because gun fire and vibration from the guns could lead to bad radar data.
In Vienna we had the V, VII and VIII Towers. Type V and VII where nearly identical in their looks, both the G and L Turm. Type VII was a bit higher than type V.
Type V is the ones we have in the Stiftskaserne (G-Turm) and in the nearby Èsterhazypark (L-Turm). The Stiftskaserne Tower is used an goverment emergency bunker today because its located very close to the parliament and its in the middle of a guards regiment barracks. The L-Tower is was used as platform for an astronomical observatory after the war but was converted to a hugeass aquarium in the late 50's.
Picture from the early 50's. It still looks the same, just with some com-dishes on the top.
G-Turm and L-Turm.
As you see the G-Turm was round and had a lot of balconies called swallows-nets for smaller 20mm Flakvierlings facing key locations in the city like parks, palces or important buildings and where supposed to fight low flying aircraft, on top of it you had 4 Zwillings 12,8-Flak 40. for engageing high altitude bombers. Lower stories where storage rooms for ammo, spare gun barrels, there was a hospital in one of the lower floors and some of the floors where used as air-raid shelters too.
The L-Turm on the other hand was a rather unspectacular big box, with not very thick walls. The first few stories of the tower where also used as air-raid shelters while the upper stories where for the radar equipment, kitchens and soldiers quarters.
You can see the L-Turm is "rather" thin, only 2,5m concrete walls and 3,5m roof, while the G-Turm had 3,5m walls and nearly 5m roof in case of ammo detonation.
One of the 2 radar dishes on the L-turm.
Todays pictures of the two towers. You can google "Haus des Meeres" for the Aquarium in the L-Turm, they got some floor plans on the Website and stuff.
The Tower-Pair No. VII in the Augarten was similar to the type 5 towers, only being around 10 meters higher. That had a simple reason too. All the decks of the towers where on the same sea level, so radar data could be synched the best possible, and since the Augarten is a bit lower, they simply made the tower higher.
The Augarten G-Turm is sadly in a very bad shape. Shortly after the war kids apparently set off around 2000 flak shells which pretty much destroyed the top of the tower (and the kids) completely. Dont ask me what the shells did up there, what the kids did up there, what both together did up there, but apparently it shattered all windows in few streets radius. Its falling apart more and more since then. Also looks very miserable on the inside, i was in it before they locked it down because of falling concrete.
Looks like this today, held together only by a bunch of steel wires in the top.
And the L-Turm, similar to the other one.
The L-Turm is in good condition, but not used either. Thou they are plaining to use it as a datacenter for servers in the future. There where also plans to build a hotel on top of it but that was canceled since the Augarten is a historic park and the city wouldnt let them build stuff there. Other plan however is to build a huge open air cinema using the tower wall as a theater canvas which i totally approve of
Type VIII in the Arenbergpark looked different than the others, the L-Turm was a bit longer and now had 3 dishes and the G-Turms gun emplacements where separated from each other completely to avoid damage to the other guns and casualties if one would take a hit. Also the guns could be lowered and raised on their platforms to conceal them even more from fighter plane fire since the tower lacked 40mm flaks.
Not round but square for whatever reason, having more space for air raid shelter and more storage room.
Picture is not from the Vienna tower but the similar built tower in Berlin. Top looked pretty much the same, only the vienna one had smaller entrances and sloped edges.
Looks like this now :
Both bunkers locked down and unsused today. Thou you could get up to the swallows nests a few years ago too to get a view over the city, but they closed that for some reason.
Well thats what i know, but i can do some research and find you some more pictures if you are interested