Kaiserwasser is an arm of the Old Danube next to Vienna International Center. There’s no entry fee and dogas are allowed, also into the water. If you arrive by U!, just turn left after exiting the subway station, under the little bridge and you’ll be there after one minute on foot. There’s public toilets and free ping pong tables. You will find groups of stundents, families and ladies with their dogs among the recreation seekers, a colorful mix of Vienna’s population.
If you look for some privacy and calmness, just head further on East and turn left across the small brigde spanning the lovely natural pond.
U1 Vienna International Center
91 A Vienna International Center
92 A Vienna International Center