The best way to explore Zurich is to rent a bike. Actually it´s the cheapest, too. You can borrow Velos [the swiss-german word for bikes] for free.
The campaign Züri rollt shall integrate youths and offers a clean way to get around the city. The bikes are new, there´s a huge system of cycle tracks and as long you´re not leaving the inner city you don´t have to climb hills.
The first day I tried to borrow a bike I had no ID with me. I payed the 20 Fr deposit and showed my press card. The guy at the station searched for the number and my nationality on “my ID card” & of course couldn´t find anything. Quickly I wrote down a random number and got the bike after some stern looks.
I cycled around the river to hang out at the jetty. The sun was shinning, it felt like summer & some guys jumped into the water. But I was right not to trust this retreat. My journey ended up in a thunderstorm with rain, eddy sunshades & grumbling thunder.