Société des transports de Tunis
The Société des transports de Tunis or Transtu is the parastatal authority to manage public mass transit in the greater Tunis area (Grand Tunis). It supervises the bus network, the Métro léger de Tunis (a light railway system) and the TGM light rail link to La Marsa. Transtu was founded in 2003 when the "Société nationale des transports" (SNT) and the "Société du métro léger de Tunis" (SMLT) were combined. Annually Transtu handles about 460 million passagers. The longest line is still line 47 History. In 1872 Tunisia's first railway was inaugurated linking Tunis  to La Goulette. The first trolley, initially horse-drawn, was opened in 1885; electrification of the trams started in 1902. A suburban train between Tunis, Bab Saadoun and La Manouba was opened in 1903. In 1930 bus service was started. By 1944, the trolleys were replaced by trolleybusses. After gaining independence, the transport systems in Tunis were nationalized. The "Société nationale des transports" (SNT) was charged to manage transit in the greater Tunis area in 1964. The Metro leger was subsequently created to provide a modern transit system without incurring the cost of building a subterrean metro. First trains on  Line 1 began to operate between Tunis and Ben Arous in 1985. In 2003 the SNT and the "Société du métro léger de Tunis" were combined. Network. The authority manages three networks: