Zurich

Location: Zürich-Limmat
Fee: use the normal ZVV-bus/tram ticket
You can do a (romantic) boat trip on the Limmat to the Lake Zürich. Start at the near of the Hauptbahnhof.

Location: Zürich
Fee: -
A very nice place about 5 min from Hauptbahnhof. Beautyfull prospect over Limmat and Old Town.

Location: Zürich
Fee: 5 CHF
If yo're interested on swiss history, than you're right here. Nice old rooms, furnitures, pictures and other things there.

Location: Zurich Old Town
Fee: various

The Old Town of Zurich is a very nice place for walking, shopping, eating, drinking and nightlife. On the left and right side of the Limmat (the small river from/to the Lake Zurich) are a lot of old and nice buildings and churches. In the small lanes of the Old Town are a lot of life during the day and night. You can get a nice prospect over the city, if you going upstairs in the tower of Grossmünster.
The prices are a little bit high for foreign tourists, but you get a good value for your money!

Location: Zurich
Fee: 0-?

You can reach Lake Zurich very easy by walk from the city, or you can take a tram to the station "Bellevue".
The cheapest thing is to do a walk on the beach. You can go to the west side (over the Quai-bridge) of the sea or to the east side. I think, that the east-side is more better, as the west side. There are some small parks on the way. There are already a lot of sitting possibilities and small take-away stands, where you can buy a cold drink, an ice or a hot-dog.
You can already hire small boats too. The taxes:
Small boats: 12-20 CHF/30 Min
Motorboats: 36-42 CHF/30 Min
On the way back to Bellevue, you can walk in the streets behind of the beach to the Theatre. On the way are some good restaurants and bars.
Europe's bigest party, the Streetparade is located on the streets around the sea on a Saturday in August.