This park belongs to the campus of the University of Zurich. I really love this place. You see all kind of people coming here, students, families, group of friends, dog-walkers, sports fanatics and so on when the weather is right. If you need a break from the hustle and bustle of the city, come here, bring you pick nick, perhaps a beer (yes, in Switzerland you're allowed to drink wherever you please) and enjoy the sun.
The newly opened (student-) bar and the university canteen offer drinks and meals which are reasonably priced- a bit more expensive if you're not a student from Zurich, but still relatively cheap.
Hirschwiesenstrasse 10, 8057 Zürich, Switzerland