The city operates a system of bus (73 lines), tram (4 lines) and trolley-bus (4 lines) routes to all districts; the  long tram system is the only tram network in Estonia. A flat-fare system is used. The ticket-system is based on prepaid RFID cards available in kiosks and post offices. In January 2013, Tallinn became the first European capital to offer a fare-free service on buses, trams and trolleybuses within the city limits. This service is available to residents who register with the municipality.