To legally fly in Austria, you have to register at the
AustroControl, which takes about 2 - 3 weeks, have insurance and pay the fee of about EUR 350 annually.
This is the official information I can give you and I know, being someone only on a trip to/through Austria, this is quite unpleasant. Even for us citizens, this approach is quite costly and not something I would expect in the year 2019, however if you hold a permit you are more or less allowed to fly everywhere (on uninhabitated land), expect where it is forbidden (for recreational purpose with a quadcopter).
Speaking of forbidden, I have other bad news for you: Vienna is complete NFZ as shown on the
map of AustroControl.
Although I can understand parts of it in the proximity of the airport, it's just another sad way to limit it to nothing. Not even 30 m are allowed.
However, being my home town and a wonderful city, it's hard to resist actually.
I therefore give you the advice certainly to stick to the rules but also show common sense. Best to avoid any problems is to get up early and use the sun rise. Stay away from crowds, respect the close airport and the helipads of surrounding hospitals.
A rather good spot is on or near the
Reichsbrücke or on the
Donauinsel. You can have a good view on the old parts of the city and the modern architecture with the UN HQ.
Or the
Prater and the close
Kahlenberg ...
If you have further questions, just ask ...
Please enjoy your stay in Vienna.
