The Rome Metro () is a rapid transit system that operates in Rome, Italy. It started operation in 1955, making it the oldest in the country. The Metro comprises three lines – A (orange), B (blue) and C (green) – which operate on of route, serving 73 stations. The original lines in the system, lines A and B, form an X shape with the lines intersecting at Termini station, the main train station in Rome. Line B splits at the Bologna station into two branches. The third line opened in 2014 and connects to the rest of the system through an interchange with Line A at San Giovanni. Rome's local transport provider, ATAC, operates the Metro and several other rail services: the Roma–Giardinetti line and the Roma–Nord line. The Roma–Lido, which connects Rome to Ostia, on the sea, used to be operated by ATAC until 1st July 2022, when it became part of the Cotral network. Lines Line A Line A runs from the southeastern suburbs of Rome, then along the northeast section of downtown, and then to the northern section of the city, near Vatican City. It connects with Line B, along with many other national and regional rail services, at Termini, and with Line C at San Giovanni. It has 27 stations, with terminals at Battistini and Anagnina. It is identified by the colour orange. Line A was the second line built in Rome. Approval was given for the construction of the city's second Metro line in 1959. Work on Line A began in 1964 in the Tuscolana area, but suffered a series of delays caused by poor organisation. Above all, the originally planned cut and cover method of construction posed serious problems for road traffic in southeast Rome. Work on the Metro was suspended and began again five years later, using bored tunnels, which partially resolved the traffic problems but caused numerous claims for compensation for vibrations caused by the machines. Work was also frequently interrupted by archaeological finds made during the excavations, particularly near Piazza della Repubblica. Line A entered service in February 1980. In the late 1990s, it was extended from Ottaviano, in the Prati district, to Battistini to the west. Since June 2022, Line A is connected with the reactivated railway station of Vigna Clara. The Vigna Clara-Valle Aurelia section is a relevant step to close the railway ring in North Rome because of