There's a unified system (www.zvv.ch) of buses, S-bahn suburban trains and, most importantly, trams. Services run from 5.30am to midnight, and tickets must be bought in advance. Every stop has a dispenser. Either type in the four-figure code for your destination or choose: a short single-trip Kurzstrecke ticket, valid for five stops (Sfr2.10; yellow button on dispenser); a single ticket for greater Zürich, valid for an hour (Sfr3.60; blue button); or a 24-hour city pass for the centre, Zone 10 (Sfr7.20; green button). Tickets from dispensers don't need to be validated before travel; all others, such as the Zürichcard, must be stamped in the yellow 'Entwerfers' on the platforms. It's a Sfr80 fine if you're caught fare-evading.
A one-day pass for the whole canton costs Sfr30. Zürich's S-Bahn trains reach Baden, Schaffhausen, Stein am Rhein, Zug and Einsiedeln, but these are beyond the reach of the cantonal ticket.
Weekend night buses (around Sfr5, passes not valid) depart from Bellevue at 1am, 2am and 3am for suburban destinations.
Parking is tricky and costly. The two most useful car-parking garages (www.parkhaeuser.ch; about Sfr32 a day) are opposite the main post office and on Uraniastrasse, next to the e-café. Otherwise street meters usually have a one-hour (Sfr2) or two-hour (Sfr5) maximum.
Taxis are expensive and usually unnecessary. It's not usual to hail them on the street; pick them up at the Hauptbahnhof or other ranks. Alternatively, call 044 444 44 44.
City bikes (www.zuerirollt.ch) may be borrowed or rented from various locations, including Velogate (7.30am-9.30pm year-round), near platform 18 at the Hauptbahnhof; outside the department store Globus (Usteristrasse; 7.30am-9.30pm May-Oct); and outside the Opera House (7.30am-9.30pm May-Oct). A passport or identity card and Sfr20 must be left as a deposit. Rental is free if you bring the bike back after six hours for a pit-stop; otherwise it costs Sfr5 a day.