The Stadtpark is gorgious. Fullstop. Its walkways are calming and it is never too crowded. The huge meadows are populated with relaxing sun bathers and the playgrounds full of happy children. There are a couple of smaller restaurants or cafés to take a sip of a latte or of the white foam of a "kühles Helles".
At this time of the year the park offers a sheer explosion of colors when follwoing the rhododendron trail. You can reach it when entering the park from the east side (where the road Alte Wöhr hits the Saarlandstrasse) and walk basically streight until you reach the little cafe opposite the rose gardens. There is a sign post then.
When done we recommend to go explore the popular beer garden of Schumacher. There is a big lake in the middle of the Stadtpark which you have already spotted on the left when walking towards the rhododendron trail. Take a tour around it towards the left and you will basically head into the beer garden. The restaurant holds nice parties in the summer and is famous for its easter fires. Also very nice is the café Sommer Terassen which is some 50 meters walk to the East, crossing the Südring. Its terrace sits directly over the Goldbekkanal and faces south. Terrific.