This place, a small pavilion with a big terrasse, is a hotspot, especially for students. It is beautifully situated in the central park and in summer it might get very crowded. They offer quite many events during weekends with local DJs and bands. Absolutely worth a visit! (Nov.- Feb. only open on weekends)
Get a beer or a "Radler" when here in summer and gaze upon the duck pond. Check their schedule for events. Entry is usually free.
In summer come here in the evening, it has a special vibe with so many people enjoying the surroundings.