Buy tickets from machines in the station, and be sure to validate them in the posts next to the ticket machines. Single tickets cost € 2.70; or save by paying €9 for four single-trip tickets, which you can validate as you need. If traveling fewer than three train stations or six bus or tram stops, buy a short-trip ticket for €1.70. Day tickets cost € 7 for unlimited travel until 3am the following day, or if you are traveling with others, a small group ticket will get up to five people unlimited travel for €17,30. For those staying longer, a pass valid for seven days may be a better value at € 30.