Construction work on the central section of Rome's Metro C between S. Giovanni and the Colosseum will begin on 15 April, according to the city's mayor Gianni Alemanno.

The seven-year project will cost €792 million and will cover a three-km stretch including two metro stops: Amba Aradam-Ipponio and Fori Imperiali-Colosseo.

Both stops are central to the success of the troubled 21.5-km Metro C which will be linked to Metro A in S. Giovanni and Metro B at the Colosseum.

On 21 March Alemanno described the Metro C project, which has been designed to connect the south-eastern suburbs of Monte Compatri-Pantano with the city centre, as "the most important infrastructure work today in Italy".

However one year ago the Audit Court president Luigi Giampaolino said Rome's fully-automated third underground line seemed set to become “the most expensive and slowest public works project in Europe and the world."

Since construction began in 1990, the cost of the project has risen from €1.9 to over €5 billion and the route remains far from completion.

The section across the historic centre from the Colosseum to Castel S. Angelo (one of the most important) has been re-planned and re-routed several times because of the discovery of important archaeological remains. One station, Largo Argentina, has been dropped completely and progress on the Piazza Venezia station, a vital stop along the way, has come to a stop because of complications with access routes.