There is a comprehensive, unified and extremely efficient bus, tram and S-Bahn service in the city, which includes boats on the Limmat River (although not cruise boats on the lake). Tickets allow you to switch between modes of transport as you like. There's a 24-hour city pass, and a 24-hour pass valid for unlimited travel within the whole canton of Zürich. Taxis in Zürich are expensive and almost always unnecessary; even high-earning bankers tend to catch the trams.