The extension takes Line C to 17.9km, 8.7km of which runs at grade, with new stations also added at Mirti, Gardenie, Teano, Malatesta, and Pigneto.

An initial 12.5km, 15-station section of the line opened on November 9 2014 and a further one station extension to San Giovanni, where the line will interchange with Line A, is expected to open by the end of the year. The line's final two stations at Amba Aradam/Ipponio and Fori Imperiali in the city centre are expected to open in September 2020.

The line is served by six-car AnsaldoBreda trains which have capacity for 1200 passengers and operate at an average speed of 35km/h.