Spend a leisurely morning brunching at Restaurant Viadukt... aaaaah. We sampled some pretty awesome pancakes here while chain-drinking delicious espressos.
Zurich is at its best in the summer, when swimming becomes part of the daily agenda. There are a variety of great places along the river Limmat, most of which are free and open to the public. When it gets too crowded at these, try to find one of the few hidden places along the lake.
For Didierea Trolli, Cyphostemma bainessii and other astonishing creatures from the family of the succulents, take a stroll through the six glasshouses, situated a bit outside the city center along the lakefront.