About 15 minutes walk from the school I was working at in Vienna, and next door to the University of Life Sciences was Türkenschanz Park (Schanz is a kind of fortification- there was a fort here at the point when the Hapsburgs and Ottomans were at war).
One of the main attractions of the park is the fake Renaissance tower (built 1908). In the summer you can climb up it and see the view, but on a wet mid-week afternoon in January it was shut.