The S-Bahn is the overland commuter trains while the U-Bahn is the underground. Trams also operate (Strassenbahn) around Vienna along with buses. A single ticket is €1.50 (€2 if bought on board) and must be validated on board to avoid the €40 fine. There are various passes available that cover the transport network such as 24HR (€5) 72HR (€12) and the Vienna Card (€16.90) with unlimitied 72hr travel and discounts of up to 50% in some shops, restaurants and entry to attractions. Tickets are available from Tabaks, ticket machines and Wiener Linien outlets.