A major milestone has been reached on the A1 motorway between Firenze Sud and Incisa–Reggello, where the final barrier separating the two sides of the new San Donato tunnel has been removed, marking the completion of the tunnel’s excavation.
The 950-metre tunnel is one of the key works in the long-running expansion of the Autostrada del Sole, designed to improve capacity and safety along one of Tuscany’s busiest stretches of motorway. According to Autostrade per l’Italia, the excavation required a total of 495,000 hours of work.
The tunnel was excavated from both ends using traditional construction techniques, allowing the existing tunnels to remain fully operational throughout the works. The section carries around 30 per cent more traffic than the national motorway average, making it a particularly important link between northern and southern Italy.
Once completed, the new San Donato tunnel will carry southbound traffic on three lanes. It forms part of the wider 18-kilometre upgrade of the A1 between Firenze Sud and Incisa-Reggello. Some 6.2 kilometres of the new motorway alignment were already opened to traffic in 2021.
The project has also included the construction of the two Ribuio viaducts, comprising separate 150-metre steel and concrete decks, as well as the new Massone viaduct near Incisa-Reggello, which consists of two separate three-span steel and concrete structures. A further 11 overpasses are due to be demolished and rebuilt.
Now that the excavation has been completed, work can now move inside the San Donato tunnel, finishing the roof and road surface, installing technological and safety systems, and building connections between the new and existing tunnels.
A further four kilometres of new motorway carriageway are also expected to open in the coming weeks, between the Chianti service areas and the San Donato tunnels. Traffic will then be transferred onto the new alignment, allowing work to begin on upgrading the original A1 carriageway.
According to the current timetable, traffic is expected to be diverted through the new San Donato tunnel within the next year, while the new three-lane sections will progressively come into operation from 2028.
The overall expansion project has a value of approximately 1 billion euro, with an average of 500 workers employed across the construction sites.
The breakthrough was attended by Deputy Prime Minister and Minister of Infrastructure and Transport Matteo Salvini, Tuscany governor Eugenio Giani and Autostrade per l’Italia CEO Arrigo Giana.
