Metro de Santiago is South America's most extensive metro system with 5 lines, 108 stations and 103 kilometres of track making it the second longest in Latin America after that of Mexico City. The metro system serves the city of Santiago, Chile. Three of the lines are rubber-tyred metro. 4-Line and 4A-Line are traditional steel wheels. The system services around 2,300,000 passengers per day. The system is administered by the state-owned Metro S.A.. Along with Metro Valparaíso in the city of Valparaíso and the Biotren in Concepción, it is one of the three metropolitan railway systems in Chile.