Vienna's 252-metre Danube Tower is the tallest building in Austria and one of the few high-rises in a deliberately low-rise city. Opened in 1964 with the Vienna International Garden Show, it has an open observation terrace at 150 metres and a slowly revolving restaurant just below.
The lift takes around 35 seconds; the view stretches across the whole city, the Danube, and the Vienna Woods. Best in clear weather; on hazy days less so. There is a bungee jump from the deck for the brave. U-Bahn: Alte Donau.