The Roma-Civita Castellana-Viterbo line (sometimes called the Roma-Nord line) began life as narrow gauge tram running from Piazza della Libertŕ in Rome to Civita Castellana. However the next stretch of the line, to Viterbo, was built as a railway and over the years the tram section was converted into a railway as well. A process which concluded with the moving of the Roman terminus from the street-level terminus at Piazza della Libertŕ across the river to a new underground station in Piazzale Flaminio, beside the subsequently constructed metro A line station, after the Second World War.
The line is currently operated in two modes: as an urban service from Piazzale Flaminio to Montebello[disambiguation needed], and as an suburban service from Piazzale Flaminio to Viterbo. The urban service operates with a frequency of about one train every 10 minutes, while the suburban service operates considerably less frequently, with less than a third of the trains making the full two and a half hour journey from Rome to Viterbo.