Yesterday I went adventuring around Wienerberg in the outer 10th District, and found this rather pretty building. I had to find out more about it, and so I went to trusty Wikipedia, and this is what it told me:
The water tower was drawn by Franz Borkowitz and built in 1898-99. It used to be a part of a bigger building complex, and supplied the areas in the 10th and 12th district that were too high up to be reached by the water in the Wienerberg reservoir. This was a time when the city was rapidly growing, and the water usage with it.
It was in use until 1956. Inside the tower nowadays there’s an exhibition space, and it’s used for events. There are free tours of the tower 7 months of the year, so if you’re super keen some googling will tell you when there is a tour next.
Last year they built a water park for kids to play in next to the tower.