The public transport system
Every city has its good points and its bad points. The public transport system is definitely one of Vienna's good points. Cheap, frequent, clean, efficient, safe and rarely overcrowded.
The four main forms of transport are U-Bahn (subway), Schnellbahn or S-Bahn (local train), Straßenbahn (tram) and Autobus (bus).
Vienna works on an honesty system. There are no ticket barriers at stations and no formal ticket checks on trains, trams and buses. You just hop on and off unchallenged. This doesn't mean public transport is free, though. You need to buy a ticket.
Now I daresay you may be wondering why you'd bother buying a ticket. And you wouldn't be the first to think that.
Leaving the ethics aside for the moment, a lack of formal ticket checks does not mean there are no ticket checks. You may suddenly find the unassuming gentleman next to you whipping out his transport authority ID and asking to see everyone's "Fahrschein."
These undercover agents are impossible to spot and they've heard all the excuses before. There's a fine for travelling without a ticket, plus the cost of a ticket. Incidentally, smoking is also banned in stations and on public transport.
Anyway, tickets are so cheap and the system so good, it behoves us all to pay up.
All forms of public transport fall under the same organization (WienerLinien), so the tickets you buy are independent of your mode of travel. If you buy a ticket from A to B, it doesn't matter if you take the tram, train or catch the bus. Or use all three to make the journey.
If you have children, those under six do not need a ticket. And those under fifteen go free if it's a Sunday, public holiday or the summer school vacation (usually eight weeks in July and August.) The latter also qualify for half-price single tickets.
Tickets are available from ticket offices in the main stations, ticket machines in stations, and from newsagents / tobacconists (Trafik). Single tickets are also sold by machines (at a premium) on trams and buses, provided you have the right coins.
Use this to validate tickets
Most tickets you buy (see below) need a stamp to be valid. You stamp a ticket by putting it into the yellow or orange slot on the small blue ticket machines (see photo) you find in trams and buses, and at the entrances to U-Bahn and S-Bahn stations.
Tip: If you get lost or forgot where your hotel is, show your stamped ticket to a tram driver or station attendant. They'll be able to tell you where you stamped your ticket, so you can retrace your journey back to the beginning.
Single ticket: Lets you travel from any point A to any point B within Vienna. The only restriction is the journey must be direct, with no break. You can change buses, trams and trains as you need, provided you're taking a continuous journey to your destination.
24-hour network card (24 Stunden Wien): The 24 hour time period starts from the time you first stamp the ticket. In that period, you can go where you like, as often as you like, within the city limits.
72-hour network card (72 Stunden Wien): Same as above, but for longer!
8-day network card (8-Tage-Karte): This ticket has 8 stripes and you stamp each one as you need (beginning with the first). Once stamped, it entitles you to travel anywhere in the city until 1am on the following day. If you stamp two strips on the same day, then two people can travel using the ticket. Three strips for three people etc.
Tip: Take care using the 8-day card. If you inadvertently stamp the strip marked number 8 first, then this means all 8 strips are used up. Fold the card so that the lowest available number is facing up and at the top of the ticket before you put it into the stamping machine (see photo).
Note also that the 8-day card isn't necessarily intended for 8 consecutive days travel. You stamp a stripe if and when you need it.
The three network cards are transferable - they're valid for the bearer and not for any one particular person. And city-wide travel means exactly that. The city zone (zone 1) covers just about anywhere you're likely to go as a visitor. You'll only enter another zone if you visit one of the surrounding towns or villages.
The Vienna card: Sold by WienerLinien ticket offices, many hotels and the tourist information offices. This is identical to the 72-hour network card, but also qualifies you for various discounts. In fact, just about any thing you're likely to visit, watch or see offers reductions with the Vienna card. See here for more info.
Tip: If you plan on taking in plenty of sights and shows, then the Vienna card pays for itself pretty quickly.
Weekly network pass (Wochenkarte): Entitles you to city-wide travel from Monday 9am to the following Monday 9am.
Monthly network pass (Monatskarte): Entitles you to city-wide travel during the relevant calendar month, plus the first two days of the next month.
Both the weekly and monthly pass are transferable, and neither requires stamping since they come preprinted with the week or month in question.
Tip: I'd strongly recommend you buy one of the network cards. They save you money once you make more than a couple of trips in a day, and once stamped you can forget about having to validate a new ticket every time you step on a tram.
Look for the "English" link on the WienerLinien website for more details on tickets, where to buy them, timetables and maps.