With the construction of
Rome–Naples Direttissima, it was decided to build a through railway ("Passante"), partly on the surface and partly underground, directly connecting the
line from Salerno with the line to Rome, without the need to reverse trains. The line would also allow the construction of several railway stations in order to create an urban metropolitan service. Although work started in 1906, it was not opened until 20 September 1925 due to delays in completing the work, mainly as a result of
World War I and the hilliness of the route. The railway consists of three stations outside the city of Naples in
Pozzuoli,
Giugliano (its station,
Giugliano-Qualiano is some distance from the centres of both Giugliano and
Qualiano) and
Quarto and six in the city at Napoli Garibaldi, Cavour, Montesanto, Amedeo, Chiaia and Fuorigrotta. The entire line was double track and electrified with 650 V DC
third rail. In 1927 the names of the stations of Chiaia and Fuorigrotta were changed to respectively in
Mergellina and
Campi Flegrei. In the same year the
Direttissima was completed connecting to the
metropolitana near
Villa Literno station and the stations of
Bagnoli and
Gianturco were opened. In 1929 the station of
Piazza Leopardi was opened. In 1935, the line was electrified with standard
Italian Railways 3 kV DC
Overhead Lines, a new station was opened at
Cavalleggeri d'Aosta and the station at
Piazza Garibaldi (beneath
Napoli Centrale) was rebuilt. Today the metropolitan trains of the
line 2 operates between Gianturco to Pozzuoli on the line. Some of them go further to
Castellammare di Stabia,
Salerno and
Caserta. Until 2009, the stations of Piazza Garibaldi, Mergellina and Campi Flegrei were also served by long-distance trains, but this severely interfered with the suburban services. ==Notes==