This place is close to Tempelhofer Feld: 1-minute-walk and you can enjoy a free space, that has the size of monaco. :)
There are many restaurants and bars around, you don't even have to leave the area for a perfect stay in berlin. :)
But if you want; to underground U8 (U Leinestrasse) it's a 5-minute-walk, 10 minutes to S Bahn circle line (S Hermannstrasse).