Rome has 2 underground lines and uses trams, buses and bike sharing for transportation with single tickets costing 1€. Barcelona has 9 underground lines, buses, trams and bike sharing called Bicing with single tickets at 1.40€. Cagliari has 1 overground line and uses buses and beach transports with single tickets costing 1€. Berlin has 9 underground lines, 16 overground lines, buses and single tickets costing 2.10€.